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cover......................................Effervescence in 0 gloss ofchampagne - dose-up ofadrop impact.page 10

CONTENTS

europhysics newsvolume 33 • number 1January/February 2002

NEWS FROM EPS

e Europeon Physical Society and fOP Sciences

Dfrecteur de 10 publieor/pn J.M. Qui/be

uropean Physical SocietyPresident Martial Duc!oy Vi/leroneuse

Executive CommitteeVice-President Per-Anker Lindgard RoskildeSe, tary Christophe RossellurichVice-Secretary Ryszard ~osnowski WorsawTreasurer Peter Reioeker UlmVice Treasurer Maria Allegrini PlsaMembeflDavid Brown SolihullGerardo Delgado Barrlo MadridKillel Gaemers LeidenDallbor ~rupa I!JUbnaChristophe lerefos ThessoJorrikl

PS SecretariatSecretary General Da'lid leed,lee@lJnfv-mulholJse,frEPS Conferences Chrlstfne-BilSilanc.basrion,@univ·mulhouse.frAccoulltant Pas(anne PildoyaniAddress EPS,34 rue Marc Sejjuin.BP 2.136, F-68(l60 Mulhouse Cedex. Francerel 33 339 3294 40 fox +33 389329449Opening times the Secretariat is open from 08.00hours to 17.00 hours French time every.day exceptweekends and French publl~ holidaysWebslte WWW.eps,oJg

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4 Snowflakes and seaweedDenis Weaire

5 Quest for superheavy nucleiP.H. Heenen and w: Nazarewicz

10 Effervescence in a glass ofchampagne: A bubble storyGerard Liger-Belair andPhilippe Jeandet...................................................................

14 The OARIGeorges Charpak andRichard 1. Garwin

17 Plectics: The study of simplicityand complexity

!':!.ur.ra1..9.~~!.~!:!:.~~.~ " .

REPORTS

22 The word from BrusselsTom EIsworth

24 An interview with Charles Kleiber. Swiss State Sectretary for Science

C. Rossel and T. lung....... " .

26 The science lecture:theatre in the round?Denis Weaire

27

28

21

29

30

32

East-West collaboration innuclear scienceWolfram von Oertzen...................................................................European Journal of PhysicsAlistair I.M. Rae

EPS Meetings Listing...................................................................Noticeboard

Book reviews

Letters

FEATURES

Snowflakes and seaweedDenis Weaire, Trinity College, University ofDublin, Ireland

electrqd~0sjt pattern

4

Treasa is currently starring as SnowWhite in Ireland's leading Christmas pan­tomime (a traditional form of popularseasonal entertainment), and may be lostto science if her budding acting careerprospers. One wonders what Grumpy'sremark would be, on being told that hisguest is a computational physicist.

DepOt legal: janvier 2002

Pr'"ter Rorofrance, lognes, Fra[\~e

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Editorial Advisory BoardCh~.irma n George MorrisonJ ~Iexfs Baraloff, Jean­P-atrick CO]Tneralle. arlos Fiolfiajs, BJII GelleUy, PrankIsrael, Marie'Claude lemalre. Peter Oelhafen,Jem o@tPeplle PE:,aer5~>n, €hrTstopf1~ Rosse!. (laud" se:b,e-nnll,Mal:ShaIl510neham,Wolffilrll von Oertzen.Jean-MatcQujJbe

155N 0531-7479155N 14U·l092 (eleetronlHllifllJn)

europhysr13 news JANUAR.v./FEBRtJAR;Y 2e02

Sometime around 1609 Johann Kepler processes may lead to compact roundedcaught what he described as a star from objects, or branching feathery ones, in so-

heaven, an individual snowflake. Its ele- called dendritic growth. If severalgant shape inspired him to write A New generations of branches are involved, weYear~ Gift or the Six-Cornered Snowflake may even approach the mathematiciansfor his benefactor, Counsellor Wackher of ideal of a fractal structure, one in whichRegensburg. It was a minor diver- detail is contained with detail, indefinitely.tissem~nt in his illustrious~ In branching out andcareer, but a remarkable one. For tending towards towards asome it even represents the N fractal structure, theorigin of crystallography. snowflake maintains its

In his essay Kepler ram- ~~ symmetry; more or less.bled amusingly from the ~~ When similar patternsseeds of the pomegran- ~ were first found inate to the cells of the ~~~~ metals they werehoneybee, picking up clues . - - called iron snow. Butto the origin of symmetric ~ln other growth processes leadnatural structures. He was led to more random structures,to a theory for the sixfold rather like seaweed inshape of the snowflake in terms appearance. Treasa Meeganofthe packing of tiny lumps ofice. These has just completed a PhD in thewere not described as atoms, but played TCD Physics Department, modellingthe same role of simple, primary con- these structures and comparing her com-stituents, out of which a complex pattern puter simulations with patterns foundwas to arise. when metals are electrodeposited. These

The same indescribable beauty was patterns are found to swirl clockwise oradmired by the Irish physicist John Tyn- counter-clockwise when magnetic fieldsdall in the 19th century. How imperfect are applied, and the research group ofseem the productions ofhuman minds and Michael Coey hopes to exploit these mag-hands when compared with those formed netic effects. They may have importantby the blindforces ofnature! But the blind- implications for the practical use of elec-ness is ours, said Tyndall, although he trodeposition in industry.correctly attributed the sixfold shape tothe way in which molecules of H 20 arearranged in the crystalline structure of ice.In his book on Forms of Water, largelydrawn from his mountaineering experi­ences in Switzerland, he also gives anaccount of flowers of ice in frozen lakes,which have a similar sixfold shape. Theyare formed when sunlight melts the sur­face of the ice.

Only in recent times was the snowflakeadopted as the universal icon of a whiteChristmas. The earliest example of its usein art is said to be on a 19th century Japan­ese sword-guard, but the ancient Chinesecertainly knew all about snowflakes, sothis assertion may well be wrong by somethousands ofyears!

The snowflake's star poses a furtherquestion. Why does it branch out, in amanner reminiscent of plants? Today wecan understand this too, as a consequenceof the growth process in which watervapour freezes on the growing flake. [Adapted with permission from an article inDepending on the precise conditions, such the Irish Times]

FEATURES

Quest for superheavy nucleiP.H. Heenenl and W Nazarewicz2-4

IService de Physique Nucleaire Theorique, U.L.B.-C.P.229, B-1050 Brussels, Belgium2Department ofPhysics, University ofTennessee, Knoxville, Tennessee 379963Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 378314Institute ofTheoretical Physics, University ofWarsaw, ul. Ho\.za 69, PL-OO-681 Warsaw, Poland

europhysics news JANUARY/FEBRUARY 2002

Historical BackgroundThe quest for superheavy nuclei began in the 1940s with the syn­thesis of atomic nuclei with a number of protons greater thanuranium (Z=92). In 1940, neptunium (Z=93) and plutonium(Z=94) were discovered. This was followed by the synthesis ofamericium (Z=95) and curium (Z=96) in 1944, berkelium(Z=97) in 1949, californium (Z=98), einsteinium (Z=99) and fer­mium (Z=100) in 1952, and mendelevium (Z=lOl) in 1955. Allthese elements were produced by intense neutron irradiations orby proton, deuteron, or helium (alpha particle) bombardment ina cyclotron. Some of these isotopes have been produced in sizableamounts. Einsteinium and fermium were discovered in thedebris from the thermonuclear explosion conducted at EniwetokAtoll in the Pacific Ocean. Amazingly, the fermium nucleus wasmade through the capture of 17 neutrons by 23BU followed by thesubsequent beta decays. In nature, a similar process (the so-calledr-process, believed to be taking place in supernova) is responsiblefor the synthesis ofheavy elements.

Still heavier elements (transuraniums) were produced inheavy-ion accelerators by fusing heavy actinide targets (plutoni­um-californium) with light ions of carbon (nobelium, Z=102,1958; ruthefordium, Z=104, 1969), boron (lawrencium, Z=103,1961), neon (dubnium, Z=105, 1967), and oxygen (seaborgium,Z=106, 1974). In order to go heavier, to compensate the decreaseof the proton-to-neutron ratio with mass, fusion of nuclei withthe largest possible surplus ofneutrons had to be used. In the 70s,"cold fusion" reactions involving medium-mass projectiles withZ ~24 and lead or bismuth targets were introduced and replaced"hot fusion" reaction with actinide targets. This enabled the dis­covery of bohrium (Z=107, 1976), hassium (Z=108, 1984),meitnerium (Z=109, 1982), ununnilium (Z=1l0, 1994),unununium (Z=1l1, 1994), and ununbium (Z=1l2, 1996). Thelast three elements are still unnamed. So far, they carry tempo­rary names derived directly from the atomic number accordingto the systematic nomenclature of the International Union ofPure and Applied Chemistry (IUPAC).

Most of the heaviest elements were found in three "heavy ele­ment factories": Lawrence Berkeley Laboratory in Berkeley(USA), Joint Institute for Nuclear Research in Dubna (Russia),and Gesellschaft fur Schwerionenforschung (GSI) near Darm­stadt (Germany). After much discussion about the priority fortheir synthesis, IUPAC 1997 has accepted names up to Z=109. At

5

The superheavy elements mark the limit of nuclear mass andcharge; they inhabit the upper right corner of the nuclear land­scape, but the borderlines of their territory are unknown. Thestability of the superheavy elements has been a longstanding fun­damental question in nuclear science. How can they survive thehuge electrostatic repulsion? What are their properties? Howlarge is the region of superheavy elements? We do not know yetall the answers to these questions. This short article presents thecurrent status of research in this field.

unknown nuclei

Fig. 1: Nuclear landscapeneutrons1 8

stable nuclei

\

82· ~known nuclei .3 - r# .

1

~-\ -t•••~ \Q 50

e0..

Nuclear Landscape

The discovery of new superheavy nuclei has brought muchexcitement to the atomic and nuclear physics communities.

Hopes of finding regions of long-lived superheavy nuclei, pre­dicted in the early 1960s, have reemerged. Why is this search soimportant and what new knowledge can it bring?

Not every combination of neutrons and protons makes a sta­ble nucleus. Our Earth is home to 81 stable elements, includingslightly fewer than 300 stable nuclei. Other nuclei found innature, although bound to the emission of protons and neutrons,are radioactive. That is, they eventually capture or emit electronsand positrons, alpha particles, or undergo spontaneous fission.Each unstable isotope is characterized by its half-life (T1/2) - thetime it takes for half of the sample to decay. Isotope half-livesrange from less than a thousandth ofa second to billions ofyears.Many radioactive nuclei may have half-lives comparable to orlonger than the age of the Earth (4.5 billion years). Examples arethe actinide nuclei 232Th (TI/2=1·101o years), 23SU (TI/2=7·108

years), or 239U (TI/2=4·109 years). Short-lived isotopes cannot befound naturally on Earth because they have long decayed sinceour planet was formed. Yet, thousands of short-lived isotopes arecontinually created in the cosmos. Their existence may be fleet­ing, but they play a crucial role in the ongoing formation of theelements in the Universe. The properties ofmost rare isotopes areunknown and can be only inferred, with considerable uncertain­ty, from theoretical calculations.

Figure 1 shows bound nuclear systems as a function of theirproton number Z (vertical axis) and their neutron number N(horizontal axis). The black squares represent the stable or verylong-lived nuclei. They form the so-called "valley of stability".The yellow region indicates shorter-lived nuclei that have beenproduced and studied in laboratories. By adding either protonsor neutrons, one moves away from the valley of stability, finallyreaching the drip lines where nuclear binding ends because theforces between neutrons and protons are no longer strongenough to hold these particles together.

FEATURES

• .4 -r - --'t "- I~. ~~- ...-(.=-...... -l ~ ......=--- - - - -- _ = _:

Fig. 2: Cross sections forthe production of theheaviest elements.Theresults of recent hotfusion experiments withthe 48Ca beam andactinide targets carriedout in Dubna are alsoshown in the box.(From Ref. [1] andYu.T. Oganessian, privatecommunication.)

116114

hot fu ionj---------j:..... t8ea !!l .._-------',

112

o Pb, Si - Targets

if' U, Pu, Cm - Targets

New discoveriesThe last three years (1999-2001) have brought a number ofexperimental surprises which have truly rejuvenated the field [1].In January 1999, scientists from Dubna reported the synthesis ofone atom of element 114 <rr:Uuq) in a "hot fusion" reactionbetween a 48Ca beam and a 244pU target. This discovery was fol­lowed by three other reports, also from Dubna. First, using the242pU (48Ca,3n) reaction, they produced 287Uuq. In 1999, the syn­thesis ofyet another isotope ofZ=114, the even-even 288Uuq, wasreported. The two a decay sequences were confirmed afterwards(July 2000, May 2001) by the observation of three a chains asso­ciated with the element Z=116 (mUuh) in the 248Cm (48Ca,4o)reaction. According to the Dubna analysis, the resulting a-decaychain goes through 288Uuq, 284Uub, and 28OlJun, which subse­quently fissions.1n neither of these cases do the a chains end upat a known isotope so a firm assignment could not be made. Con­sidering the exponential trend seen in Fig. 2 for Z s 114, it actually

106 108 110

Flement nlJmbp.r104

"

102

'0-14r-'-',---r--,----,-,---r--,-----,-.,--....--,----r-,--..,---,--!

that time, nuclei with Z=110, 111,and 112, discovered at GSI, werealready known. The lifetimes of theheaviest elements were found to bevery short. For instance, elementZ=112, investigated using the reac­tion 70Zn + 208Pb ...... 277Uub + In,turned out to have a half life of only

10-~about 280 JJsec. The corresponding C

fusion cross section is extremely ~ '0-10

small, 1 pb. Since the production ""-cross section was found to be rapidly I:) '0-11

decreasing with the atomic number,see Fig. 2, it was then concluded thatitwould be very difficult to reach stillheavier elements.

As far as theory is concerned,major advances were made in 1966,when the first realistic theoreticalcalculations for the superheavynuclei were carried out. These earlycalculations were' based on the shellcorrection (or: macroscopic-microscopic) method in which thetotal binding energy was decomposed into a smooth part(approximated by a macroscopic liquid drop model) and amicroscopic quantal shell correction term strongly oscillatingwith the number of nucleons and reflecting the energy stabiliza­tion due to the presence of nucleonic shells. Such calculationspredicted the nucleus with Z=114, N=184 (mUuq) to be a dou­bly magic center of an island of long-lived superheavy nuclei.This result stayed practically unchallenged until the late 1990swhere more refined models, based on self-consistent mean-fieldtheory and realistic effective nucleon-nucleon interactions, start­ed to be systematically applied to superheavy nuclei. In anotherfrontier of superheavy element research, in quantum chemistry,relativistic effects in molecules containing heavy elements havebeen studied intensively since the mid 1970s, when it becameapparent that they have to be included in the description of com­pounds containing heavy elements.

Chart of the Nuclides 2001

:;78 176

172

114

Fig. 3: The upper end of thenuclear chart in the region of theheaviest elements.The a chain

associated with the element mUuh, recently discovered(May 8, 2001) in Dubna in the 248Cm (48Ca,4n) reaction, isshown in the upper left corner. (From Ref. [1] and Yu.T.Oganessian, private communication.)

-, ..- r

m:ff ._---!-'U'.N

113113

161 la 1113 , ...

1511 180

. ,. ,i __. !

111 :m: :'Urn. : I

1H1'" '110 t10 ~10 Ut":OJ'~IIl.j\OO, s :1.1 51 1, I ~:IIlI'm. mtj

'12112

El

lUilPI.l'~,

----'IIttW

1,'.'10110

111 111

event #5: May 8, 2001 I=-j291116 .....-

1O.54MeV 4n

55m. /n9.80MeV ~IM7, );:--I

Pell

9.1J M.V "'m152.62.

: ----J a,~ :0<,.1liC

7~~

6 europhysics news JANUARY/FEBRUARY 2002

FEATURES

Fig. 4: a-decay chain of 277112165 predicted in the HFBcalculations with the SLy4 Skyrme interaction.The individual one­quasineutron states are labeled using the asymptotic Nilssonquantum numbers.The allowed alpha transitions are indicated byarrows. Calculated Qa values are compared to experimental datafrom GSI. (Taken from S. (wiok etal., private communication.)

112' (611]512' 161J1312'f611J ==

1312' 716 mU2160

a decay of 277112165

Experiment: 208Pb+'OZnTheory: HFB+SLy4

~:{ml1312' 1716]= 0..=11.9 MeV

3121:[611"'110 1"1>: n.7 MeV112' 16201 163 11.9 MeV3/z+ 6ZZJ __ Q..=I J.I M.V7/Z+ [6131 -= 10.3 MeV9/Z+~16151 _ Exp: ll.3M<\'lI!Z'I72S] ""108'61 9.9 M.V

1fi'162Oj Q.,=9.1 MeV~n: tm _ Exp: 9.4 MeV

712+ [6131112' [725 "'106,5'+

Qa=8.7M.V112' 1620] 8.3 MeV

1112' [725) = Exp: 8.9 M<V312+[622J =7/2+7613

'''104",1112- Ins] _ 0..=8.2 M.V

8.6M.V712' (6131 bp' 8.7 M.V112'(620 =312+ (622J "'102...

slightly different spin-orbit interaction. The experimental deter­mination of superheavy nuclei from this region will thus be ofextreme importance for pinning down the fundamental questionof the spin-orbit force.

Does it actually make sense to talk about "magic superheavynuclei"? A recent theoretical work [3] sheds a new light on thisquestion. According to calculations, the patterns of single-parti­cle levels are significantly modified in the superheavy elements.Firstly; the overall level density grows with mass number A, as exA113. Secondly, no pronounced and uniquely preferred energygaps appear in the spectrum. This shows that shell closures whichare to be associated with large gaps in the spectrum are notrobust in superheavy nuclei. Indeed, the theory predicts thatbeyond Z =82 and N =126 the usual localization of shell effectsat magic numbers is basically gone. Instead the theory predictsfairly wide areas of large shell stabilization without magic gaps.This is good news for experimentalists: there is a good chance toreach shell-stabilized superheavy nuclei using a range of beam­target combinations.

Some of the observed a-decay chains attributed to elements112 and 114 are believed to link odd-Nnuclei. The presence ofanodd neutron adds to a theoretical uncertainty. Since the single­particle level density of transactinides is large, there are manycandidates for low-lying one-quasiparticle states in parent anddaughter nuclei. Moreover, many alpha transitions are structural­ly forbidden since the properties of one-quasiparticle excitationsin parent and daughter nuclei often differ dramatically. As anexample, Fig. 4 shows the predicted a-chains for the nucleus271112 found at GSI. The Hartree-Fock-Bogoliubov calculationsexplain two observed a branches, attributed experimentally toz73110, in terms of transitions between negative parity and posi­tive parity single-neutron orbitals.

came as a great surprise that hot fusion reactions with a 48Cabeam could produce a significant number ofevents. Another sur­prising (and exciting) result of the Dubna experiments was thatnuclei which were produced have fairly long lifetimes. Forinstance, the lifetimes reported for the elements 284Uub and280Uun are many orders of magnitude longer than those of theisotopes with Z ~ 112 previously discovered at GSI.

Progress has also been made in the region previously exploredby GSI. The GSI group found a new even-even isotope of Z70Uun,and also mUuu and 271Uub. A group led by scientists from thePaul Scherrer Institute (PSI) observed the Z69,Z70Hs decay chainsat GSI, thus convincingly confirming the data on z77Uub forwhich z69Hs is a member of the decay chain. New isotopes ofz66,Z67Bh have been found at Berkeley. As far as chemistry is con­cerned, a tremendous achievement and a true tour-de-force werethe first chemical studies of seaborgium, bohrium, and hassium(see below). Figure 3 shows the upper end.ofthe nuclear chart asof2001.

Physics at the limit of cross sections is difficult and challeng­ing. The synthesis of the new element Z=118 (Z93UUO),announced in 1999 by the Berkeley group, has been retracted twoyears later. The history of heavy element research remembersother cases of elements discovered and gone, and sometimes dis­covered again. A team working in Stockholm at the NobelInstitute of Physics reported in 1957 an isotope with atomicnumber 102. The group proposed the name Nobelium in honorto Alfred Nobel. In 1958 a group at Berkeley reported that theywere unable to reproduce this work, findings agreed by a Russiangroup at Dubna. But the name stuck...

Structure of the 5uperheavy nucleiThe structure of superheavy elements results from the interplaybetween the strong and electromagnetic forces. Unlike in lighternuclei, the Coulomb interaction cannot be treated as a small per­turbation atop the dominating nuclear interaction; it doesinfluence significantly proton and neutron distributions[2].

The stability of heavy and superheavy elements has been alongstanding fundamental question in nuclear science. Theoreti­cally, it has been shown that the mere existence of nuclei withZ > 102 is entirely due to quantal shell effects. Indeed, in the clas­sicalliquid drop picture, the shape of a nucleus is governed by aninterplay between surface tension (proportional to N/3, trying tomake the nucleus spherical) and Coulomb repulsion (propor­tional to ZZIA1I3, trying to make the nucleus deformed). At largevalues of ZZIA, the Coulomb force is so strong that the nuclearliquid drop becomes unstable to surface distortions and it fis­sions spontaneously. It is the stabilization brought by quantalshell effects that is responsible for the superheavies.

In spite ofan impressive agreement with experimental data forthe heaviest elements, theoretical uncertainties are large whenextrapolating to unknown regions of the nuclear chart. In partic­ular, there is no consensus among theorists with regard to thecenter of the shell stability in the superheavy region. Since inthese nuclei the single-particle level density is relatively large,small shifts in the position of single-particle levels (e.g., due tothe Coulomb or spin-orbit interaction) can be crucial for deter­mining the shell stability of a nucleus. While mostmacroscopic-microscopic (non-self-consistent) approaches pre­dict Z=114 to be magic, most self-consistent calculations suggestthat the center of the proton shell stability should be moved up tohigher proton numbers, Z=120, 124, or 126. For the neutrons,most non-relativistic calculations predict magic gaps at N=184while the relativistic mean-field theory yields N=l72 - due to a

europhysics news JANUARY/FEBRUARY 2002 7

FEATURES

Chemical properties of superheavy elementsSince atomic relativistic effects scale approximately with Z2,chemical properties of transactinides cannot be properlydescribed by non-relativistic quantum mechanics. However,experimental tests of relativistic effects and of anticipated devia­tions from the periodic table of the elements in the superheavyregion are extremely difficult because the single atom chemistryrequires half-lives of the order of one second, i.e., much longerthan those of the heaviest elements found so far. Another obstacleis very small production rates: a few events per day for hassiumand less for heavier elements. In spite of these difficulties, therehas been major progress in the chemical characterization oftransactinides. Special techniques, such as gas phase separation,have been devised to perform one atom-at-a-time chemistry andto deduce thermodynamical properties of new elements [4].

In 1993, chemical studies of dubnium demonstrated that itdoes not behave like tantalum, the element from the group towhich dubnium was supposed to belong. On the contrary, the fol­lowing chemical studies of Sg (year 1997), Bh (2000), and Hs(2001) confirmed relativistic calculations predicting their behav­ior to coincide with that expected on the basis of their positionsin the periodic table. Hassium, for instance, forms a gaseousoxide similar to that of osmium, which places it in group 8. As oftoday, the periodic table has been experimentally established upto element 108. However, preparations cue under way to carry outgas chemistry of element 112, which instead of behaving like itslighter transition metal homologs (Zn, Cd, Hg) is expected tohave properties of a noble gas like Rn or Xe; a first attempt tochemically identify element Z=112 has recently been carried outin Dubna. Still heavier elements, predicted to be noble volatilemetals, are also excellent candidates for gas chemical studies, pro­vided that their half-lives are sufficiently long. In particular, thereis hope of employing chemical methods for the firm identifica­tion of the alpha-chains oflong-lived isotopes ofZ=114 and 116observed in Dubna.

First predictions of the chemistry ofsuperheavy elements weremade in 1971, and the first relativistic molecular calculations forsystems involving transactinide elements were published in 1977.Since then, calculations based on the relativistic quantum theoryhave been considerably improved and applied to many atomsand molecules [5]. Relativistic effects in transactinides are crucialand show up in several ways. Most importantly, 5 and P1l2 atomicorbitals contract relativistically. The shrinking of the inner shellsresults in an increased screening of the nuclear charge, and thisgives rise to an expansion of the P3/2 and of higher angularmomentum orbitals. Another relativistic effect is a change in thespin-orbit coupling. Both can produce drastic rearrangements oforbital levels. That is what is predicted to happen for element 112.Recent calculations indicate that the 75 orbital should be shiftedbelow the 6ds/2 orbital due to relativistic effects. It is the large rel­ativistic stabilization of its valence 75 orbital, combined with itsclosed shell electron configuration, that has led to the predictionthat element 112 is chemically inert.

Chemistry of the superheavy elements with Z > 118 is believedto show relativistic effects that are so large that comparison withlighter elements or nonrelativistic results is meaningless.

Borders of the superheavy region

Where are the borders of the superheavy region? What are theproperties of the heaviest nuclei that can be bound (at least, intheory), in spite of the huge disruptive Coulomb force?

As a consequence of their saturation properties, nuclear forcesfavor values of the internal density close to the saturation densityofnuclear matter. On the contrary, since the Coulomb interactiontends to increase the average distance between protons, theCoulomb energy is significantly lowered by either the creation ofa central depression or by deformation, or by both. Based on thisgeneral argument, one expects the formation of voids in heavynuclei. Recently, the subject ofexotic (bubble, toroidal, band-like)configurations in nuclei with very large atomic numbers has beenrevisited by self-consistent calculations.

Box 1: The nucleus is a complicatedmany-body system. The strong forcesdescribing heavy nuclei are stronglyaffected by the in-medium effects;they are usually approximated by

. phenomenological effective density­dependent interactions fitted to a fewkey nuclear properties. This strategy,well known in condensed matterphysics, turned out to be extremelysuccessful. The self-consistent densityfunctional theories (relativistic andnon-relativistic) describe bulk nuclearproperties such as masses, radii, shapes,as well as nuclear excitations.A numberof effective interactions have beenintroduced and their capability todescribe properties of exoticradioactive nuclei is one of the majorchallenges in present-day nuclearstructure.

Any theoretical model aiming atmaking predictions in an unknown ter­ritory should first be tested in knownregions of the chart of the nuclides.

Since the main decay mode for theknown heaviest elements is a decay, oneof the crucial quantities determininglifetimes ofthe heaviest and superheavyelements is the a-decay energy. The Qavalues for the heaviest elements calcu­lated with the self-consistent modelwith the SLy4 effective interaction aredisplayed in Fig. 5. They are comparedwith known a-decay energies. It is seenthat the agreement with experimentaldata (including the recentdata showninFig. 3) is very good, and this suggeststhat calculations such as those shownon Fig. 5 can be used to predict proper­ties ofunknown superheavy nuclei.

Fig. 5: Qa values for even-even nuclei with96 s Zs 118 obtained in the self-consistentcalculations.They are compared toexperimental data (closed symbols)including the recent data for Z=114and116. (Taken f(om S. (wiok et al., Phys. Rev.Lett. 83(1999) 1108, and to be published.)

20

18

134

124 (

·126 1?R .111"• ,1 L~ J'J22 K1I H ..

11 G PO114' .\"

J J2,

144 154 164 174 184

Neutron Number

8 europhysics news JANUARY/FEBRUARY 2002

FEATURES

"7.3(3.

318ol1 (4)

3666(7)

~133

4562

254102 No152

';.0..2+_-4-__1106

.!'-14+_-+__,,,,

2...··--m---S1 •21 .. 1 (2)

6' 3054+ 11 1159.1 (3)_+_~-::- 146

! ==~~p------«

',,-0'_--1-__"0

2!!.18-+_-+__2342

(201----T----- (2841)

I

I'"I

""'-'--+--'886

O.ll8

0.:2

0.04

0.28

0.16

014

010

0.00

~2N

Box 2: In spite of the fact that the number of protons andnucleons in the nucleus is rather small, and nucleonicvelocities are fast, atomic nuclei exhibit collective modessuch as rotations and vibrations. Manynuclei emit photonscharacteristic of the sequential de-excitation of rotationalbands. In quantum mechanics, collective rotation can onlyarise for systems that have a deformed shape, Le.,nonspherical distribution of the nucleonic density. It hasbeen only recently that rotational photons could bedetected iJi spectroscopic studies of the transactinides.First results on the collective properties of nobeliumisotopes 252.254No have been obtained at Argonne (USA)and Jyvaskyla (Finland). Ithas been found that the groundstate rotional band of 254No, the best deformed nucleusabove 208Pb, resists fission up to a spin of at least 20 1i (seeFig. 6). Detailed microscopic calculations have shown thatthe fission barrier ofthis nucleus changes veryweaklywithangular momentum, thus explaining this amazing stabilityofthe nobeIiums as a combined effect ofthe Coulomb andCoriolis-plus-centrifugal forces.

Fig. 6: Experimental confirmation of the role of deformation in transactinides was recently obtained for 254No. The figure (right portion) showsa cascade of transitions characteristic of the rotation of a deformed nucleus. From the precise energy difference between successive states, it isinferred that 254No has a football-like shape with an axis ratio of4:3, in agreement with theory.The fact that states with angular momenta ashigh as 20 1i were detected underscores the remarkable resilience of the shell effects against the centrifugal force and fission. Modern nuclearstructure calculations - such as the one labeled HF+Sly4 (left) - tell that stability comes in specific cases from the ability ofthe nucleus todeform. Here, the deformation parameter fh characterizes the elongation of the nuclear shape (for (32=0 nucleus is spherical).

106

100

124

130

118

N 112

Spinning the heaviest elements

-------------_.._---

The calculations predict the competition between several ofthese forms for the central nuclear density due to the huge elec­tric charge. It is difficult to say at present whether these exotictopologies can occur as metastable states. Will the spherical bub­ble minimum undergo the shape transition to the "band-like"configuration? What is the stability of all these shapes to reflec­tion-asymmetric and triaxial deformations? It is possible thatthere exist isolated islands of nuclear stability, associated withvery exotic topologies of nuclear density, stabilized by shelleffects.

PerspectivesThe heavy element research has been traditionally concentratedin three laboratories: Berkeley, Dubna, and GSI. But the excitingnew discoveries brought new players to the "superheavy" com­munity: RlKEN (Japan) and GANIL (France). Chemical studiesof transactinides are also being carried out at PSI and JAERl(Japan).

One of the most important and urgent tasks facing experi­mentalists will be to confirm the new elements found in Dubna.This will not be easy, since these nuclei form an isolated island,disconnected from the known region of the nuclear chart. Inorder to identify the elements beyond Z=112, new tools, such asdirect mass measurements or chemical studies must be devel­oped. How to reach even heavier nuclei? The new-generationhigh-current stable-beam accelerators will certainly be helpful inmaking new discoveries at a picobarn level. However, in order toexplore new, more neutron-rich superheavy regions, acceleratedbeams of radioactive neutron-rich nuclei will have to be utilized.It is hoped that the new high-powered ISOL facilities will enableus to explore the theoretically crucial region of nuclei betweenthe deformed N= 162 shell and the spherical N=184 shell.

There are also many challenges facing nuclear theory ofsuper­heavies. The currently highly phenomenological models used to

europhysics news JANUARY/FEBRUARY 2002

describe heavy-ion fusion are not reliable when extrapolatingoutside the regions of known nuclei. The situation is not betterfor the description of static fission barriers and of dynamics offission. Slightly better is the situation in the theoretical modelingof nuclear structure of transactinides, where the microscopicself-consistent models can make quantitative predictions. Here,the main problem is how to extrapolate density-dependent effec­tive interactions to the superheavy "terra incognita" and how todescribe exotic forms of nuclear existence created thanks to thehuge Coulomb force and the borders of the superheavy region.The advances in computer technology and in numerical algo­rithms will certainly be crucial for the success of this task.

This research was supported in part by the US. Department ofEnergyunder Contract Nos. DE-FG02-96ER40963 (University ofTennessee), DE-AC05-000R22725 with UT-Battelle, LLC (OakRidge National Laboratory), the Polish Committee for ScientificResearch (KBN) under Contract No. 2 P03B 040 14, and NATOgrant PST.CLG.977613.

References

[1] S. Hofmann and G. Miinzenberg, Rev. Mod. Phys. 72 (2000) 733.

[2] S. Cwioketal.• Nucl.Phys.A611 (1996) 211.

[3) M. Bender, W. Nazarewicz, and P.G. Reinhard, Phys. Lett. B515(2001) 42.

[4] J.v. Kratz, in Heavy Elements and Related New Phenomena, Eds. W.Greiner and R.K. Gupta (World Scientific, Singapore, 1999) p. 129.

[5] P. Schwerdtfeger and M. Seth, Relativistic Effects ofthe SuperheavyElements, Encyclopedia of Computational Chemistry; Vo!' 4 (Wiley.New York, 1998). p. 2480; V.Pershina et al. in Heavy Elements andRelated New Phenomena, Eds. W. Greiner and R.K. Gupta (WorldScientific, Singapore, 1999) p. 194.

9

FEATURES

Effervescence in a glass of champagne:Abubble storyGerard Liger-Belair* and Philippe ]eandetLaboratoire d'renologie, faculte des sciences de Reims, France*: Corresponding author, e-mail: gerard.liger-belair@univ-reims.fr

People have long been fascinated by bubbles and foamsdynamics, and since the pioneer work of Leonardo da Vinci

in the early 16th century, this subject has generated a huge bibliog­raphy. However, only very recently, much interest was devoted tobubbles in champagne wines [1]. Small bubbles rising throughthe liquid, as well as a bubble ring (the so-called collar) at theperiphery of a flute poured with champagne, are the hallmark ofthis traditionally festive wine, and even if there is no scientificevidence yet to connect the quality of a champagne with the fine­ness of its bubbles, people nevertheless often make a connectionbetween them. Therefore, since the last few years, a better under­standing of the role played by each of the numerous parametersinvolved in the bubbling process has become an important stakein the champagne research area. Furthermore, in addition tothese strictly enological reasons, we also feel that the area ofbub­ble dynamics and especially the area of collapsing bubbledynamics could benefit from the simple but close observation ofa glass poured with champagne.

In this paper, our first results concerning the close observationof the three main steps of a champagne bubble's life are sum­marised, i.e. the bubble nucleation, the bubble ascent and thecollapse of a bubble bursting at the free surface of the liquid. Ourresults were obtained in real consuming conditions, in a classicalcrystal flute pouredwith a standard commercial Champagne wine.

Bubble nucleationIn the case of Champagne wines, the main gas responsible forbubble production is carbon dioxide, which is produced byyeastsduring the second fermentation in the closed bottle. According toHenry's law, equilibrium progressively establishes between thegas dissolved into the wine and the gas into the vapour phase inthe headspace under the cork. At the end of fermentation, theCO2pressure under the cork is around 6 atm., and the wine maycontain up to 12 g/L of dissolved CO2.When the bottle is opened,the CO2pressure in the vapour phase suddenly falls. The thermo­dynamic equilibrium of the closed bottle is broken, and the winebecomes supersaturated with CO2molecules. To recover a newstable thermodynamic state corresponding to the atmosphericpressure, champagne must degas. When champagne is pouredinto a glass, two mechanisms enable dissolved C02 molecules toescape from the supersaturated liquid medium: diffusionthrough the flat free surface of the liquid, and bubble formation.As soon as a liquid medium is supersaturated, the bulk free ener­gy per unit of volume, 6.gv, associated with the transfer ofdissolved gas molecules into the vapour is negative, and thereforethermodynamically favourable. But the bubble productionprocess also results into the production of interfacial free energy.Below a critical radius re depending on some physicochemicalparameters of the solution, the bubble embryo formation resultsin a net increase of the total free energy of the system. Hence­forth, classical nucleation is characterized by an energy barrier to

10

A gas pocketentrapped insidethe particleclearly appear

100 ~m

fl9Jl Close-up ofa particle acting as a nucleation site on thewall of a glass poured with champagne. Most of these particlesare hollow elongated and roughly cy~ndrical fibres. .

overcome [2]. Therefore, homogeneous bubbl~nucleation withinthe liquid bulk or heterogeneous nucleation on smooth surfacesrequires very high supersaturating ratios, which are totally unre­alistic in the case of Champagne wines [3,4]. In weaklysupersaturated liquids, such as champagne, sparkling wines andcarbonated beverages in general, bubbles need pre-existing gascavities with radii of curvature greater than the critical radius inorder to overcome the nucleation energy barrier and grow freely.In this type of non-classical heterogeneous nucleation, dissolvedgas molecules spontaneously diffuse through the meniscus ofpre-existing gas cavities.

Contrary to a generally accepted idea, nucleation sites are notlocated on irregularities of the glass itself. The length-scale ofglass and crystal irregularities is far below the critical radius ofcurvature required for the non-classical heterogeneous nucle­ation. Most ofnucleation sites are located on hollow and roughlycylindrical exogenous cellulose fibres coming from the sur­rounding air or remaining from the wiping process. Because ofgeometrical and hydrophobic properties, such particles are ableto entrap gas pockets during the filling of a flute and thus to startup the bubble production process. A typical nucleation site is dis­played in figure 1. The gas pocket entrapped into the particle andwhich starts-up the bubble production process clearly appears.Such particles are responsible for the clockwork and repetitiveproduction of bubbles that rise in-line into the form of elegantbubble trains [5-7]. This cycle of bubble production at a givennucleation site is characterised by its "bubbling" frequency. The

europhysics news JANUARY/FEBRUARY 2002

FEATURES

time needed to reach the moment ofbubble detachment dependson the kinetics of the CO2 molecules transfer from the cham­pagne to the gas pocket, but also on the geometrical properties ofthe given nucleation site. Now, since a collection of particleshapes and sizes exists on the glass wall, the bubbling frequencymay also vary from one site to another. Three minutes after pour­ing, we measured frequencies ranging from less than 1 Hz up toalmost 30 Hz, which means that the most active nucleation sitesemit up to 30 bubbles per second. o

where the added-mass coefficient CAM is the ratio of the sur-rounding volwne of liquid displaced during ascent to the bubble CD· 1volwne. The equation of motion of champagne rising andexpanding gas bubbles can therefore be written under the form,

Since the bubble radius expands during the rise, this equationreduces to,

G. liger-Belalr 1999

o

o

0

0

0

0

0Fig. 2: Typical photographof a regular bubble train. 0

The dark line running Q

horizontally through the 0

picture is due to the liquid 0

meniscus between the free~

11 mm.surface and the glass wall.

.

(1)

d( ) 4 3 1 2 2- MoU =-pgnR -Cv-pU nRdt 3 2

a viscous drag force exerted by the surrounding fluid. This dragforce is classically expressed by

pU 22

FD =CD--nR2

where CD is a dimensionless drag coefficientt • Inertia of bubblescan obviously be neglected, but during the rise, bubbles induce adisplacement of the surrounding fluid in their vicinity, whichleads to an added-mass force. The added-mass of a bubble is

4 3Mo = CAM p-nR

3

Bubble riseA short examination of the typical regular bubble train presentedin figure 2 is already very instructive. It appears clearly that bub­bles grow during ascent. Moreover, as the distance between twosuccessive bubbles increases, and since bubbles are released fromthe nucleation site with clockwork regularity, it can be guessedthat a bubble accelerates when rising through the liquid. In orderto better analyse hydrodynamic and physicochemical parametersthat control bubble ascent, let us write the equation of motion ofan expanding spherical gas bubble, rising in a low viscous fluid,as in the case of champagne bubbles. After release from its nucle­ation site, a bubble experiences, in addition to the buoyancy

4 3FB =pg-,.R

3

.E.i9..11 Normalised drag coefficient experienced by champagnebubbles during ascent as a function of the Reynolds number Re(and indirectly as a function of the travelled distance hfrom thenucleation site); fluid sphere limit (- - - -); rigid sphere limit (- -);normalised drag coefficient that a bubble of fixed radius wouldexperience (-).

4 3(dU 3U dR) 4 3 I 2 2C p-nR -+-- =-pglfR -C -pU lfRAM 3 dt R dt 3 D 2

(2)

It was nevertheless found that the added-mass effect of a bubbleapproaching the free surface never exceeds 2-3 % of its buoyancy[5-7]. As a result, it will be neglected in the following. Thus, the

t R is the bubble radius, U is the rising velocity, p is the liquid density,and g is the acceleration due to gravity.

o 10 20 30 40

Re

50 60 70

h

80

>

europhysics news JANUARY/FEBRUARY 2002 11

FEATURES

12

equation of motion (2) reduces itself to the classical balancebetween drag force and buoyancy. Now, for each bubble of agiven bubble train, the experimental determination of R and Uleads to the experimental determination of the drag coefficientCD along the rise, through the expression,

Fig. 4: Reconstructed time sequence illustrating six stages of thecollapse of a single bubble at the free surface.The time intervalbetween each frame is around 1 ms.

1mm

Bubble collapse at the free surfaceWe report now results concerning bubbles collapsing at the freesurface of champagne. A reconstructed time sequence illustrat­ing four stages of the collapse of a single bubble is presented infigure 4. Photographs reproduced here were taken immediatelyafter the rupture of a bubble cap [11]. A brief description of eachframe follows.

content is lower in beer, growth rates of beer bubbles are lowerthan those of champagne. As a result, the dilution effect due tothe rate of dilatation of the bubble area may be too weak to avoidthe rigidification of the beer bubble interface.

Between the frame 1 and 2, the thin liquid film, which consti­tutes the emerged part of the bubble, has just ruptured (on atime-scale of 10 to 100 f!S). During this extremely brief initialphase, the bulk shape of the bubble has been frozen. A nearly mil­limetric open cavity remains at the free surface. While collapsing,the bubble cavity gives rise to a high-speed liquid jet above thefree surface (frames 3 and 4). Near the base of the liquid jet, one

- can distinguish an extremely small bubble (around 100 fllll),probably entrapped during the collapsing process. Due to its ownvelocity, this upward liquid jet becomes unstable and breaks upinto droplets called jet drops (frame 5). The combined effects ofinertia and surface tension give droplets various and often amaz­ing shapes. Finally, droplets ejected by the parent bubble recovera quasi spherical shape (frame 6). Due to surface excitations fol­lowing bubble collapse, capillary wave trains centred on thebursting bubble are propagating at the free surface. On the rightside of the central bubble, the tiny bubble entrapped during col­lapse can be observed.

The liquid jet that follows a bubble collapse strikingly resem­ble, in miniature, that one can observe as a drop impacts the

europhysics news JANUARY/FEBRUARY 2002

(4)

(3)

c = 8gRD 3U 2

Bubbles with a fully mobile interface behaving hydrodynamicallyas fluid spheres will exhibit values of Cn close to zero, whereaspolluted bubbles behaving hydrodynamically as rigid sphereswill have values of Cv close to one. In figure 3, the normaliseddrag coefficient of champagne bubbles was plotted as a functionof Re, for bubbles of various bubble trains. After a first regimeattributed to both inertia and wall effects where CD> 1, it appearsclearly from figure 3 that bubbles reach a quasi-stationary stageintermediate between that of a rigid and that a fluid sphere (butnevertheless closer to that of a fluid sphere). This result drastical­ly differs from the result classically observed with bubbles offixed radii rising in surfactant solutions. Actually, surfactantsprogressively adsorb at the surface of a rising bubble thusincreasing the immobile area of the bubble surface. Therefore,the drag coefficient experienced by a rising bubble of fixed radiusprogressively increases, and inexorably reaches the rigid spherelimit when the bubble interface gets completely contaminated.Strictly speaking, the complete immobilisation of the interface ofa bubble rising in a surfactant solution is reached before its com­plete coverage, as demonstrated by Ybert and di Meglio [9]. Inthe case of a champagne bubble, since the bubble expands duringits rise through the supersaturated liquid, the bubble interfacecontinuously increases, and therefore continuously offers newlycreated surface to the adsorbed surface-active materials (around5 mg/L, mostly composed of proteins and glycoproteins).Expanding bubbles experience two opposing effects. Figure 3suggests that the bubble growth during ascent approximately bal­ances the adsorption rate of surface-active compounds on therising bubble.

We also compared the behaviour of champagne bubbles withthat of beer bubbles. It was found that beer bubbles showed abehaviour, very close to that of rigid spheres [5-7], thus confirm­ing a previous study (10). This is not a surprising result, sincebeer contains much higher amounts ofsurface-active macromol­ecules (of order of several hundreds mg/L) likely to be adsorbedat a bubble interface than champagne. Furthermore, since the gas

During the last decades, many empirical or semi-empirical equa­tions have been proposed to approximate CD for bubbles in freerise. Some of the most popular are listed in the book of Clift et al.[8). Our measurements were compared with two of them, respec­tively CRS and CFS, available in the whole range of Reynoldsnumbers Re covered by champagne bubbles. CRS concerns rigidspheres, and is applicable for rising bubbles completely coveredwith surfactants, whereas CFS was obtained for fluid spheres, i.e.bubbles with a fully mobile interface free from surface-activematerials.

In order to indirectly access the bubble surface state during therise, the normalised drag coefficient CD defined as follows was used,

FEATURES

Fig. 5: Close-ups of two liqUid jets that follow respectively, abubble collapse (a),and a drop impact (b).

flower-shaped structures [14]. During the stretching process,energy is supposed to be mainly stored as surface free energy. Asystematic image analysis of numerous time sequences condu<;t­ed with an high-speed video camera demonstrated an averageincrease M of 15 % within approximately 300 J.1S ofbubble areasadjacent to collapsing bubbles. During the stretching process,stresses in a distorted bubble-cap (one petal of the flower-shapedstructure) can be evaluated as shown below in equation 5.

By comparison, in a previous study, a numerical model con­ducted to stresses of the order of 104 dyn cm-2 in the boundary

I. bFig. 6: Oblique view of the collateral effects on adjoiningLUbbles of a bubble collapsing at the free surface.

tt liE is the corresponding surface energy in excess during the stretching process, V is thevolume ofliquid in the emerging bubble-cap, yis the champagne surface tension(.. 50 mN/m),A is the emerging bubble area, and eis the thickness of the thin liquidfilm of the bubble-cap (oforder of 10-6-10-7 m) [15].

1 cm1mm

At a millimetric scale, such a violent hydrodynamic phenome­non which leads to the projection of a high-speed liquid jet isdriven by the capillary pressure gradients arising in the layeraround the open cavity left by a bursting bubble. Immediatelyafter the rupture of the bubble cap, the sides of the open cavitybecomes a region of positive curvature. It ensues a ring of highpressure on the sides of the open cavity. At the same time, due toa negative curvature, a low pressure zone exists around theunderside of the cavity. As a result, fluid is rapidly drawn from thesides to the axis of symmetry. The underside of the cavitybecomes a region ofhigh pressure. This pushes fluid upward anddownward to produce two liquid jets.

Since the first photographic investigation published about fiftyyears ago [13], numerous experiments have been conducted withsingle bubbles collapsing at a free surface. But, to the best of ourknowledge, and surprising as it may seem, no results concerningthe collateral effects on adjoining bubbles of bubbles collapsingin a bubble monolayer have been reported up to now. Actually,effervescence in a glass of champagne ideally lendsto a preliminary work with bubbles collapsing in a Equation 5tt:

bubble monolayer. For a few seconds after pouring,the free surface is completely covered with a mono­layer composed of quite monodisperse millimetricbubbles collapsing close to each others. Pho­tographs displayed in figure 6 were takenimmediately after the rupture of a bubble cap.Adjoining bubble-caps are literally sucked towardthe lowest part of the cavity left by the burstingbubble, leading to unexpected and short-lived

surface of a pool of liquid. In his book <CA Study of Splashes",Worthington, presented remarkably sharp photographs of dropsimpacts [12]. Shape details of two various liquid jets, producedduring a bubble collapse and during a drop impact are displayedin figure 5. Hydrodynamic structures arising after a drop impactare clearly very close to those which follow a bubble collapse.Since hundreds of bubbles are bursting every second during thefirst minutes of champagne-tasting, one can conclude that thefree surface of a glass of champagne is literally spiked with suchcone-shaped liquid structures, unfortunately too short-lived tobe observed tQ the naked eye. .

europhysics news JANUARY/FEBRUARY 2002 13

FEATURES

layer around an isolated millimetric collapsing bubble [16]. Thisis a brand-new and slighdy counter-intuitive result. Whileabsorbing the energy released during collapse, as an air-bagwould do, adjoining bubble store this energy into the thin liquidfilm of emerging bubble-caps, leading finally to stresses higherthan those observed in the boundary layer around single milli­metric collapsing bubbles. Further investigation should beconducted now, and especially numerically, in order to betterunderstand the relative influence of each pertinent parameters(bubble size, liquid density and viscosity, effect of surfactant... )on bubble deformation.

Contrary to what could have been thought at first glance, effer­vescence of champagne turned out to be a fantastic tool toinvestigate a first approach of the physical chemistry of risingand collapsingbubble dYnamics.As we do, we hope that the read­er will now look at the effervescence in this traditionally festivewine, not only as a nice visually appealing phenomenon, but alsoas a very instructive one in terms of bubble dynamics study. Itwould have been regrettable not to have a closer look at such adaily phenomenon, before considering a more academicapproach under certainlybetter controlled, but also less seducingconditions.

AcknowledgmentsThanks are due to the EuropoI'Agro institute and to Jean-ClaudeColson and his association "Recherche Oenologie ChampagneUniversite" for financial support, to Champagne Moet & Chan­don and Pommery for supplying wines, and to VerrerieCristallerie d'Arques.

The above article is an updated version of a previous articlepublished in the "Bulletin de la Societe Fran~se de Physique"vo!. 127, pp. 9-11, (2000/2001).

References[1] M.Vignes-Adlcr, Bulletin de la S.F.P. (SocieteFran~ de Physique)

106,27 (1996)

[2] M.Blander,Adv. Colloid Interface ScL10, 1 (1979)

[3] P. M. Wilt, J. Colloid and Interface Sci. 112, 530 (1986)

[4] S. F. Jones, G. M. Evans, K. P. Galvin, Adv. Colloid Interface Sci. 80,27(1999)

[5] G. Liger-Belair et al., Langmuir 16, 1889 (2000)

[6] G.Liger-Belair,Bulletin de la S.F.P. 127,9 (2000/2001)

[7] G. Liger-Belair, Une premiere approche des processus physico­chimiques lies al'effervescence des vins de Champagne, PhD Thesis,University ofReims, France (2001)

[8] R. Clift, J. R. Grace, M. E. Weber, Bubbles, Drops and Particles, Acad-emic Press, NewYork, (1978)

[9] C.Ybert and J.-M. di Meglio, Eur. Phys. J. BA, 313 (1998)

[10] N. Shafer and R. Zare, Physics Today 44, 48 (1991)

[11] G. Liger-Be1air et al.,Am.J. Enol.Vitic. 52, 88 (2001)

[12] A. M. Worthington, A study ofsplashes, Longman & Green ed.,London, (1908)

[13] A. H. Woodcock, C. F. Kientzler, A. B. Arons, D. C. Blanchard, Nature172,1144 (1953)

[14] G. Liger-Belair, M. Vignes-Adler, B. Robillard, P. Jeandet, C. R. Acad.Sci. Paris serie IV (Physique-Astrophysique) 2,775 (2001)

[15] J. Senee, B. Robillard, M.Vignes-Adler, Food Hydrocolloids 13, 15 (1999)

[16] J. M. Boulton-Stone and J. R. Blake, J. Fluid Mech. 254, 437 (1993)

14

TheDARIAunit of measure suitable to the practical

appreciation of the effect of low doses of

ionizing radiation

Georges Charpak1 and Richard 1. Garwin2

1 CERN Laboratoire 1,1211 Geneve 23, Switzerland2 Philip D. Reed Senior Fellowfor Science and Technology, Councilon Foreign Relations, 58 East 68th Street, New York, NY 10021

A clearer understanding by a wider public ofthe health effects ofradioactive materials arising in the nuclear industry is essen­

tial ifthe public interest is to be served. Even clear and continuousinformation provided to the public about radiation dose fromindustry is inadequate to an intuitive and correct understanding ofrelative risk-:- in part because radiation exposure is expressed inunits that non-specialists find difficult to comprehend.

We propose the establishment of a unit of irradiation dose tothe individual that is equal to that provided tQ a human being bythe naturally occurring radioactivity of human tissue: the"DARI;' from the French for "Dose Annuelle due aux RadiationsInternes"- annual dose from internal radioactivity.

To the extent of 90%, this radiation is due to potassium 40, ofhalf-life 1.3 billion years, which was present in the cosmic dustfrom which the Earth was formed about 4.5 billion years ago.

The DARI amounts to less than 10% of the natural radiationto which the body is subject, arising from external irradiationfrom rocks and from cosmic rays. The use of this unit forexpressing the individual's radiation dose from an incident or anaccident involving radioactive materials would facilitate a properjudgment of its impact, and would avoid unwarranted concerns.

In the physical sciences an impo.rtant role is played by units ofmeasure that permit an easy appreciation of the order of magni­tude of the items measured.

The metre, the kilogram, and the second were thus adopted inengineering. In fields in which the order of magnitude of theobject studied are much smaller or much larger, it has been nec­essary to introduce auxiliary units adapted to daily practice. It isthus in astronomy or in microscopy; where one uses the light­year, or the angstrom and the nanometer.

Over the last few decades there has been a massive increase inuse of ionizing radiation. There has been a corresponding evolu­tion of units for the measurement of the intensity of sourcesemitting radiation and for evaluating their effect on the humanbeing.

The extreme sensitivity of instruments to measure radioactiv­ity, detecting even the disintegration of a single atom, has ledpractitioners, in their particular fields, to deal with figures thathave a substantial number of zeros. Thus the becquerel (Bq) isthe intensity of a source in which one atom on the average disin­tegrates each second; it is used for weak sources, while themegacurie is often used by an engineer dealing with nuclearwastes- the curie (Ci) being the intensity ofa source in which 37billion atoms disintegrate each second- hence 3.7 x 1010 Bq.

Evaluating the effect of radiation on the human body involvesmore complex questions. The nature of the ionizing radiation­alpha particles, betas, gammas, heavy ions- makes it necessary

europhysics news JANUARY/FEBRUARY 2002

to take into account the great variation in the deposit of energyalong the trajectory of the particle and on its effectiveness in dis­turbing the genetic material of living cells. The mechanismsinvolved in these effects are still a matter of debate, and the exis­tence or not of a threshold for harm gives rise to argument.

Current units of irradiationThe accepted units, which are employed by various individualsand groups needing to make decisions regarding the acceptabledoses of radiation, both for the public at large and for workers inthe field, are based on the energy deposited by the ionizing radia­tion. But they are hardly helpful in providing an intuitiveestimate of the nature and hazards of radiation. In this regard, letus just note that the lethal dose of radiation for a human involvesthe deposition of energy that raises the temperature of the bodyby a mere thousandth of a degree.

The gray (Gy) corresponds to the deposition of 1joule per kg ofliving tissue. One takes into account the different sensitivity of thevarious human organs by weighting the deposit of energy by acoefficient of effectiveness, which leads to the definition of thesievert (Sv). Finally, although it is a matter of reasonable agree­ment that the lethal dose is four or five Sv for a human being,regulatory authorities interpret the available facts on the induc­tion of lethal cancer by low doses of radiation as giving aprobability of cancer linear with the dose, without a threshold ofharm for a human being. Specifically, that estimate is 0.04 lethalcancers per Sv of whole body irradiation. Such a coefficient per­mits the prescription of permissible levels of irradiation to havean acceptable risk for the various populations, when weighedagainst benefits to the economy or to the public health in the useof radiation, for instance for the diagnosis or treatment ofdisease.

Proposal for a new unit linked to the irradiation of thehuman body by its own natural radioactivity-the OARIWe suggest an approach that may lead to a more intuitive estima­tion of the impact of low doses of radiation. The unit that wepropose provides a much more immediate idea of the risks runby a given level of irradiation. It is as rigorous as the units usedthus far, to which it can be related in a precise fashion. We suggestthe "DARI;' for "Dose Annuelle due aux Radiations Internes­(annual dose due to internal radiation)". This is close to the irra­diation experienced during a single year by an individual, due tothe radiation emitted by the radioactive materials present in thehuman body that have nothing to do with any line of work. TheDARI is to be defined as 0.2 millisieverts, precisely, although theannual dose itself is about 10% less.

The two principal radioactive substances that contribute tothis internal irradiation are potassium-40 (a natural isotope thatis a permanent component of living tissue), and carbon-14 pro­duced in the air by cosmic rays and which is present in all livingorganisms.

We prefer this standard of internal radiation to one represent­ing the average human irradiation from all natural sources thatcorresponds to a level about ten times larger than the unit pro­posed. This total varies too much with geography and altitude toserve as a reasonable standard.

Our interest in a standard such as the DARI arises from thefact that even much weaker irradiations than this internal expo­sure give rise to futile controversy and can distort crucial choicessuch as those that concern energy supply for centuries to come.

First we discuss more extensively the origin of this internalirradiation, which will permit us to estimate readily the scale ofcertain incidents or accidents related to nuclear power.

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Natural sources of internal and external irradiationOur planet was formed by the aggregation of the dust from deadstars. All of the chemical elements that compose the Earth weresynthesized through the nuclear reactions that take placethroughout the life ofsuch stars. Certain elements are radioactivewith a mean life in hundreds of millions or billions ofyears andare always present.

Uranium, thorium, and potassium play an important role increating the molten core of the Earth. The energy of their radia­tions has melted and maintains the molten sphere of iron-nickel,some 3500 km in radius, which constitutes the core ofour planet.

These primordial radioactive wastes are present everywhereon Earth. Potassium-40, which is a natural isotope of potassium,has a half-life of 1.3 billion years. It pervades living organisms,and the human body of 70 kg mass is host to about 6000 Bq­i.e., 6000 disintegrations per second.

Uranium is widely distributed on Earth and constitutes about3 millionths by weight of the Earth's crust. Its presence in rockscontributes a significant portion of the natural irradiation tohuman beings. It also contributes to this total by the radioactivityof one element in its decay chain- radon-222 (of half life 3.8days), which is a noble gas emitting alpha particles. Radon isresponsible on average for more than half of the natural irradia­tion of humans; the U.S. government recommends effectiveventilation of homes in order to reduce the level of radon frombuilding materials or from seepage from the underlying rock.

Nuclear energy and public healthUranium has a special importance since the discovery of nuclearenergy. By use of uranium fission in a nuclear reactor, as muchenergy could be extracted from the uranium ofanygiven portionof the Earth's crust as if it were pure coal.

Of course, because of the cost of extraction of uranium from .such lean deposits, it is currently obtained from the much small­er deposits of higher grade ore- ranging from 0.1% to 14%uranium by weight. But studies show that it is possible to obtainuranium from seawater (where it constitutes only about 3 bil­lionths by weight) with a cost that is a mere 15 times larger at themoment than that required to obtain uranium from the depositsthat now serve to feed nuclear power plants. Uranium from sea­water thus gives an affordable and practically unlimited supply offuel for fission power.

In the future, which in the more or less long term is threatenedby the exhaustion ofthe energy resources based on fossil fuel, it isthus legitimate to consider the major role that can be played bynuclear energy. This is particularly true considering theenhanced greenhouse effect from the carbon liberated to theatmosphere by the normal combustion of coal, oil, or even natur­al gas. However, the enormous amount of radioactivity producedin the course of releasing energy from fission, raises inevitablequestions and anxieties about the danger for our generation andthose to come, by the massive deployment ofnuclear power.

The degree to which nuclear power is accepted depends uponthe resources of the individual countries, but also upon a realisticevaluation of the dangers and problems the various alternativeenergy sources present to the human species. Decisions are ren­dered more difficult by the sometimes irrational character of thedebates concerning the effects on humans of ionizing radiationofvarious origins, to which we are exposed, voluntarily or not.

A major problem right now for the nuclear industry is to showthat it is capable of caring for radioactive waste from nuclearpower plants in a satisfactory fashion for generations to come,and is able practically to eliminate the possibility of a major

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catastrophe like that at Chernobyl in 1986.To make a proper judgment of various proposed courses of

action, it is helpful to take into account the irradiation to whichhumans are exposed independently of nuclear energy.

Relative importance of natural sources of irradiation,internal or externalRadiation from internal sources is an absolute floor below whichit is impossible to sink. Natural radiation overall, about ten timeslarger, represents a level to which we should refer to evaluate thelimits imposed on exposure from the nuclear industry, and inorder to evaluate the seriousness of incidents or accidents. Wewill now examine several sources contributing to natural radia­tion, using as the unit of irradiation the sievert or the thousandthof a sievert- millisievert (mSv). Cosmic rays shower the Earthand provoke nuclear reactions in the upper atmosphere, causedby the energetic protons of the cosmic rays. At sea level the cos­mic rays contribute an annual irradiation about 0.5 mSv. Theintensity increases with altitude, which on average contributesmore irradiation in a year to airline crews than is legally permit­ted for workers in the nuclear industry- 20 mSv per year.

In the atmosphere, cosmic rays transmute nitrogen intoradioactive carbon- carbon-14, with a mean life of 5000 years;C-14 is present in the form of carbon dioxide within the atmos­phere. Incorporated by plants into their tissues, carbon-14pervades all living things, and along with potassium-40, presentsince the beginning of the Earth, contributes the most importantand least avoidable part of internal radiation. For a person of 70kg weight, carbon-14 contributes about 4000 becquerel; togetherwith the 6000 Bq from potassium-40, one has thus an activity of10,000 Bq in the average human being. Taking into account therelative biological effectiveness of this radiation on differentorgans, this source of 10,000 Bq contributes about 0.17 mSv peryear. Incidentally, it is the same 0.17 mSv per year for a child andfor an adult of whatever weight, since it is the energy depositedper kg that is measured by the Sv- 1 joule per kg.

Now we compare this level to the total irradiation experiencedby humans from other natural sources, totalling, as indicated,about 2 mSv per year. One needs to take into account the radioac­tivity of the soil containing more or less radioactive material­notably potassium and uranium. In France itself, there is a vari­ability of a factor 3 from 1 mSv in the environs of Paris to 3 mSvin Brittany. On our planet, there are vast populated regions wherethe natural radioactivity is much greater. Added to the exposurefrom rocks, there is the radioactivity due to radon, and the cos­mic ray intensity that varies with altitude.

Natural irradiation ofthe average American citizen, like that ofthe French, amounts to about 2.5 mSv per year, to which must beadded the irradiation due to medical diagnostics- on the orderof 1 mSv per year on average. The variation in natural radioactiv­ity within France, about 1 mSv per year, exceeds the limitimposed by the law on the exposure of the civil population by thenuclear industry. At this level, it has not been possible thus far todemonstrate any impact on public health; there is no direct evi­dence ofharm caused by irradiation of this magnitude.

It seems to us instructive to choose as a practical unit ofirradi­ation close to that due to the unavoidable K-40 and C-14 in thebody, amounting to 0.17 mSv per year, which is quite uniformamong the world's population. We have rounded this to 0.20 mSvper year and called it the DARI, for "Dose Annuelle due aux Radi­ations Internes (annual dose due to internal radiation)".According to the International Commission on Radiation Pro­tection (ICRP), exposure to a DARI conveys a probability of

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incurring lethal cancer of ten parts in one million. If a lethal can­cer corresponds to 20 years of life shortening, each DARI thencosts the individual one hour of life expectancy. This calculationis rejected by some who believe in the existence of a threshold,below which there is no harm from radiation. In either case, onehour is little enough to pay for the gift of a body inherited fromthe stars and the cosmic rays.

The natural variability from place to place amounts to fiveDARI or more. Nevertheless, we should not countenance theaddition of even one DARI to the individual's radiation burdenwithout considering the benefits to that individual and to society.

Table 1 demonstrates the relative importance ofvarious wide­spread sources of irradiation.

Table 1. The relative importance of various widespread sources ofirradiation

O.lDARI Dose received In France on average from the nuclear power Industry

SDARI The soil in the environs of Paris on average

10DARl The soil in Brittany on average

5DARI Cosmic rays ats~ level (increase of I DAR! per 50 m at altitude).

5DARl Average diagnostic radiography'

5DARI Limit established for the irradiation Ofthe pUblic by the nuclear

industry.

40DARI Single CAT scan

500DARI Annual maximum dose, for 5 successive years, for a worker in the

nuclear industry.

25,OOODARI Lethal dose for the average human

300.000 to 500.000 Dose delivered as local irradiation to treat a cancer.

DARI

*The DARI is intended to represent an effective dose. If 2milligray ofgamma radiation is delivered to the left side of the body, the equivalent(and effective) whole-body dose is one millisievert or 5 DARI. Accordingto the linear hypothesis for the effects of low doses of radiation, thesame probability of cancer will result as if one millisievert weredelivered to the whole body - although any tumour will appear onlyon the left and not the right side of the body. Asimilar approach appliesto the effect of a small diagnostic dose of radioactive iodine - effectsof which would be limited to the thyroid but which could be expressedin equivalent whole-body dose in microsieverts or DARI.

The exposure limit of 500 DARI imposed on a worker in thenuclear industry corresponds to a reduction in life expectancy(500 hours) equal to that produced by the smoking of ten ciga­rettes per day during that same year.

This risk of cancer to a worker receiving the maximum per­mitted dose in the nuclear industry should be compared with theoccupational risks associated with other industrial or commer­cial activities. For example, driving an automobile in trafficexposes the driver to carcinogenic exhaust fumes (especially par­ticulate matter) with a greater risk of cancer.

Recently one has seen in France polemicS over accidentalreleases of radiation whose impact is less than one hundredth ofa DARI, exposing only a local population to this tiny augmenta­tion in irradiation.

The DARI puts in perspective these polemics, of which theimpact on the political scene and in the media is disproportion­ately large compared with the substance. The debate shouldcentre on the following problems as regards future energy:

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FEATURES- --: -_ --=---._.'~- ~ ::-'_ -0:::::--_-=--_ -= -=- -.-• What are the real and comparative hazards ofvarious sources

of energy now available to humanity?

After the exhaustion of the fossil energy supplies, what are theoptions then?

We are expecting 9 billion humans in the middle of this century,compared with 6 billion at this moment. In the industrializedcountries, about 20% of the population die of cancer. Among thesources of cancer about half have been identified as due to lifestyle- tobacco, alcohol, obesity, diet-and seem avoidable.About 2% of cancers are thought to arise from carcinogenicmaterials used in industry, or from automobile exhaust fumes.

One must be alert to reduce to a minimum all of these haz­ards-especially the more important ones. Those that are due toradioactivity are among the easiest to measure, and they must bemaintained at an acceptable level. A unit of measure which takes

into account the unavoidable natural self-irradiation of a humanbeing seems appropriate, bearing in mind that it has not beendirectly demonstrated to have an effect on health.

According to the severe criteria used by regulatory authoritiesto evaluate the impact of radiation on public health, the DARIshortens life by about one hour per year. And the French accord­ingly lose six minutes per year because of their dependence onnuclear power-assuredly less than the hazard of the coal alter­native. The table shows, however that there is substantial merit inreducing the exposure to the average individual from diagnosticX-rays, which by the same calculation shortens life by an averageoffive hours per year.

Georges Charpak received the Nobel Prize for Physics 1992 and isMembre de I'Academie des Sciences. Richard L. Garwin is amember ofthe US National Academy of Sciences.

Plectics: The studyofsimplicityandcomplexityMurray Gell-Mann, Santa Fe Institute,Santa Fe, USA

The subject that I call plectics is the study of simplicity andcomplexity. At the Santa Fe Institute, which I helped to start,

we deal to a great extent with matters of simplicity and complexi­ty. I arrived at the name, plectics, in the following way. The word"complex" comes from plexus, originally meaning braided, andcom-, meaning together, hence braided together. "Simple" comesin a similar way from roots meaning once folded; and the Latinwords for "braided" and "folded" both owe their ultimate originto the Indo-European root *plek-. In Greek, that root gives rise toplektos, meaning braided. So, in using the word plectics we aredescribing the subject ofsimplicity and complexitywithout com­mitting ourselves as to whether we are talking about somethingsimple (once folded) or something complex (braided together).

What do we mean by complexity and its opposite, simplicity?It would take a great many concepts, a great many quantities tocapture all the various meanings implicit in our use of the wordcomplexity. But there is one concept - what I call effective com­plexity - that represents most closely what we usually mean ineveryday conversation and also in scientific discourse when weuse the word. A non-technical definition of effective complexitywould be the length of a highly compressed description of theregularities of the entity under consideration. Compression ­the elimination of redundancy - is very important; otherwisethe length of the message would be ofvery little concern to us.

In my book"The Quark and the Jaguar" I describe the elemen­tary school teacher who assigned to her class a 300-word essay tobe turned in on Monday. One pupil, who spent the weekend play­ing around outdoors (as I would have done as a child), hastilyscribbled the following on Monday morning: "Yesterday theneighbours had a fire in their kitchen, so I leaned out of the win­dow and yelled "FIRE, FIRE, FIRE, FIRE, ... " Of course he couldhave compressed that description by saying "I leaned out of thewindow and yelled FIRE 282 times", but the teacher insisted on a300-word essay. Now, one way to discuss compression is to makeuse of the concept of algorithmic information content. It isdefined for a string ofbits, that is a string of zeros and ones, or anentity that is described by that string of zeros aild ones. The algo-

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rithmic information content is the length of the shortest programthat will cause a given universal computer U to print out that bitstring and then stop computing.

Any kind of definition that utilises the length of description,even the length of a very concise description, will still involve acertain amount of arbitrariness or context dependence. We aredescribing a certain entity and the description is coded into a bitstring. The level of detail at which we are describing the entityobviously matters. In physics that is called the coarse graining.The language in which the original description is expressed mayalso matter, and certainly the assumed knowledge and under­standing of the world are important. All of these things help todetermine the length of description. When the description isthen coded into a string of bits to be printed out by a computer,we have additional context dependence, through the coding con­vention and also the choice of the universal computer. But ifweput up with all that context dependence, we can give a more tech­nical definition of effective complexity: the algorithmicinformation content of the regularities of an entity. That means

. that the entire algorithmic information content of the entity issplit into two terms - one describing the regularities and theother describing the remaining features, which are regarded asincidental or random

Ties and bitsLet me use neckties as an example. The length of description ofregular ties is trivial - you just give the colours, widths, andspacings of the stripes and the background colour of the tie, andyou have it. But, of course, we are making a distinction herebetween the regularities in the pattern and various other featuresof the tie that we are treating as random or incidental, for exam­ple soup stains or little irregularities in the weave, and so on andso forth... Those are not included in the description.

Ifwe are just concentrating on the regularities in the pattern ofother ties, this by contrast, is quite complex. For a hand-paintedtie from Austin, Texas, describing the regularities of its patternwould take a long time. It has a high effective complexity.

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For a hand-painted tie...

describing the regularities

of its pattern would take a

long time. It has a high

effective complexity.

Let us consider a bit string consisting entirely of ones. It isobviously simple, since describing its regularity is so easy. It has avery low effective complexity as well as a very low algorithmicinformation content.

At the other end of the scale of algorithmic information con­tent we would have a long bit string with almost no regularities- an incompressible or "random" string of zeros and ones, withno regularities except the length. Its algorithmic informationcontent is very high, in fact maximal for the length of the string.The shortest program to describe it would be one that says"Print" followed by the string. Even though it has the greatestpossible algorithmic information content, its effective complexityis again very small, because there are no regularities except thelength.

So at both extremes, for the very simple string and for the verymessy one, we have low effective complexity. Effective complexitycan be large only in between, for something that lies between theextremes of order and disorder, something that has lots of differ­ent regularities.

Now, there can be no well-defined mathematical procedurethat is guaranteed to find all the regularities ofa bit string or ofanentity described by it. In general we identify regularities bymeans ofshared information, known technically as mutual infor­mation. If we process a bit string in certain ways and find thatafter processing it we can divide it into two or more parts andthose parts share a lot of information, then we conclude thatthere is regularity present. While mutual information is diagnos­tic of regularity, it does not supply a measure of the algorithmicinformation content of the regularities that are present, and somutual information is quite distinct from effective complexity.

Although there are mechanisms for identifying regularity,there is, as I indicated already, no mathematical procedure thatwill guarantee finding all the regularities. Thus the effective com­plexity, the algorithmic information content of the regularities,depends to some extent on who or what is describing the entity.

Let's go back to the necktie, when we were discussing the effec­tive complexity of the pattern and ignoring the various kinds ofstains. However, suppose that we are dry-cleaners. We wouldn'tcare so much about the pattern; we would concentrate instead onthe soup stains, the blood stains, the winestains, and so on. Those are the regularitiesthat are most important for the dry-cleaner.

What are the systems that identify per­ceived regularities and then compress theirdescription into a brief message? They arewhat I call complex adaptive systems, onesthat learn or adapt or evolve as living thingsdo. Each of us is such a system, capable ofidentifying perceived regularities in the datastream reaching us and distinguishing themfrom what is perceived as random or inci­dental, and then compressing the descriptionof those regularities into a briefmessage.

We can give a description of how a complex adaptive systemfunctions. It takes in a stream of data about the world, includingitself. Certain regularities are identified in data that it has alreadytaken in, and those regularities are then compressed into a verybrief message, which I call a schema. This schema can be used, incombination with further data from the stream, to describe fea­tures ofthe world, predict the behaviour of things in the world, orprescribe behaviour for the complex adaptive system in theworld. But then there are consequences in the real world: thedescription is better or worse; the predictions come true or they

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fail; the prescription for behaviour in the realworld results in success or failure, survival or dis­appearance. Those consequences in the realworld then feed back to exert selection pres­sures on the competition among variouscandidate schemata. CA schema, although ithas to have some degree of stability orrobustness, must also be capable ofchanging, of undergoing mutation orreplacement by another schema.)

Complex adaptive systems andlifeAll of the examples on Earth ofcomplex adaptive systems, atleast all the ones we know of,are connected in some waywith life, although theyare not necessarily aliveor even parts or aggre­gations of livingsystems. Also, theyhave a tendency togive rise to othercomplex adap­tive systems.

Among thecomplex adaptivesystems on ourplanet were the pre-biotic chemicalreactions that led to life in the firstplace. Then biological evolution is acomplex adaptive system, and so is the

behaviour of each individual organism \~~ii~~Yresulting from biological evolution. Partsof organisms can also function as complexadaptive systems - for example our immunesystem. The functioning of the human brain,

giving individual learning and thinking, isalso a complex adaptive system. Then wemay look at the behaviour of organisedgroups of people: human cultural evolutionin general is a complex adaptive system, andhuman organisations, such as business firms,evolve as complex adaptive systems.

There are also non-living complex adap­tive systems. Our computers are nowsophisticated enough so that complex adap­tive systems can be established oncomputers, usually by the use of software.Where is the connection with life? It's gener-ally agreed that the nerds who perfect the

software for these complex adaptive systems on computers areactually living things.

Now, what are the schemata? Well, let's take a very familiar com­plex adaptive system involving many human beings, namely thescientific enterprise in which most ofus are engaged. The schema­ta are theories. The theories are robust and when they have successin predicting properties of the real world they generally survive.When observations that are done carefully and are repeated overand over again disagree with the theory, then the theory is likely tobe modified or have another one substituted for it.

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Besides the scientific enterprise, where the schemata are theo­ries, we may consider biological evolution, where the schemataare genotypes, and the evolution of a human society, where theschemata are laws, traditions, myths, customs, and so forth.Those schemata are composed ofunits that Richard Dawkins haschristened memes, analogous to the genes in biological evolu­tion. Sets of memes are the cultural DNA for societal evolution.

Let's return to the complex adaptive systems on computers.There are genetic algorithms, based on a very crude analogy withbiological evolution. There are the so-called neural nets on com­puters, whieh are based on a very crude analogy with the way thatthe human nervous system - in particular the brain - is thoughtto operate. But there could be many more. We might have dozensof different kinds of adaptive computation methods, and theydon't have to be based on analogies with ideas about the brain orbiological evolution. There must be a wide class of possible com­plex adaptive systems on computers. What is that class? Whichmembers of that class are suitable for solving which problems?We know that there are some problems for which genetic algo­rithms are suitable, while for others they are not. The same forneural nets - there are certain optimisation problems, for exam­ple, for which neural nets work very well, while there are othersfor which they don't. It can be shown that there is no complexadaptive system on computers that would be good for all optimi­sation problems. Each one has its domain of applicability, and itis a great challenge to theory to understand the whole class ofcomplex adaptive systems on computers and figure out whichone is good for which kind ofproblem.

Now I should point out, as a warning, that not everyone usesmy notation. John Holland, who was the original inventor ofgenetic algorithms and a colleague and friend, uses a differentterminology. What I call a complex adaptive system is somethinglike what he calls an adaptive agent. What I call a schema he callsan internal model. Also, he uses the term complex adaptive sys­tem to mean what I would call a loose aggregation of complexadaptive systems that are modelling one another. (Examplesinclude a market composed of investors and an ecological systemcomposed of organisms.) By using different terminologies, weare both illustrating the famous adage that a scientist wouldrather use another person's toothbrush than another scientist'snomenclature.

Sometimes apparent complexity does not reflect high effectivecomplexity. Besides the length of the shortest program that willcause a fixed universal computer to print out a description of theregularities of the entity in question, we must also consider howlong it takes that computer to go from a briefprogram to printingout the description. That is called the logical depth ofthe regular­ities, as discussed by Charles Bennett.

Apparent and effective complexitiesTake, for example, the energylevels of atomic nuclei. The rules forthose energy levels look, at first sight, as if they are very compli­cated, but we now believe that they are obtained from a couple ofsimple physical theories: quantum electrodynamics (the quan­tum field theory of electromagnetic interactions) and quantumchromodynamics (the quantum field theory of quarks and glu­ons). We believe that ifyou put these two together you will get adescription of atomic nuclei in great detail, including the posi­tions of all their energy levels. But the computations areextremely long and difficult on our existing computers, usingknown methods, and most of them haven't even been done yet.So here is a case where we are looking at something apparentlycomplex that has in fact low effective complexity, but a lot of log-

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ical depth. In other words, a short program is involved, but thatprogram is associated with a very long computation time.

Consider a case where we are still not sure whether apparentcomplexity reflects effective complexity or logical depth. Do theuniversal features of biochemistry on Earth constitute a uniquesystem? Or are there many different kinds of possible bio­chemistries for systems resembling life that mayflourish on otherplanets, orbiting other stars, in other parts of the universe? Itdoesn't look as if there is anything particularly special about oursolar system or our planet or, for that matter, life, which appearedsoon after the heavy bombardment of the Earth came to an end.It is most likely; therefore, there are very many planets in the uni­verse with something like life, that is, complex adaptive systemswith a chemistry resembling in some way the biochemistry onEarth. But do those chemistries have to be the same? Or is there awide class of possible biochemistries? We don't really know andthe experts disagree.

Some of them think that the fundamental constraints ofphysics limit biochemistries to just a very few possibilities. Othertheorists believe that there are many possible biochemistries, ofwhich we happen to have one example here on Earth. Ifwe acceptthe ideas of the first set of theorists, then biochemistry has loweffective complexity because it is derivable from the laws ofphysics. That derivation might be lengthy; however, implying a.good deal oflogical depth. If the other theorists are correct, thenbiochemistry on Earth could have some appreciable effectivecomplexity, since it would depend as much on accidents ofhisto­ry as on fundamental physics.

This brings up the matter ofhow complexity arises in the uni­verse. Where does effective complexity come from? We who workon the fundamental laws of physics mostly believe, as I do, thatthose laws are extremely simple. There are two of them. The firstis a unified theory ofall the elementaryparticles and all the forcesof nature. It may be that we already have that theory; in the formof the wonderful candidate that has evolved from superstringtheory into what is now called"M Theory?'

The other fundamental principle ofphysics is the initial condi­tion of the universe near the beginning of its expansion, some tenbillion years ago. That may also be simple. In fact some specificideas have been proposed about ways in which it could be simple.

A hundredyears ago, we would have said that, given the funda­mental theory and the initial condition, we could in principlepredict the history of the universe. But today we know that is notthe case. Our theories are probabilistic rather than fully deter­ministic. Thus the history of the universe is co-determined bythese two fundamental principles and by an inconceivably longsequence of accidents - chance events - with various possibleoutcomes. In advance ofeach event, only probabilities for the dif­ferent outcomes are available. A very simple example from thelaboratory is the disintegration of a radioactive nucleus, emit­ting, for example, an alpha particle. The direction in which thatalpha particle will come out is completely unknowable before itemerges; all directions are equally probable. When it does comeout, then it is possible to discover the direction of emission.

We can think of the alternative, suitably coarse-grained histo­ries of the universe as forming a branching tree, withprobabilities at each branching. As time goes on and a givenbranching is reached, one of its branches is selected. Before thebranching occurs, however, there are only probabilities for thedifferent alternatives.

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Frozen accidents and the history of the universeThe wonderful Argentinian writer, Jorge Luis Borges, wrote ashort story called"The Garden ofForking Paths", in which some­body built a model of the branching histories of the universe inthe form of such a garden.

Just think of all the accidents that have given rise to us in thisdiscussion group: the little fluctuation that produced our galaxy;the accidents that were responsible for the formation of the solarsystem; the accidents that determined the character of the Earth;the accidents early in the history of the Earth that gave rise to life;all the accidents ofbiological evolution, which, together with nat­ural selection, have produced the life forms on Earth today,including human beings; and then the accidents of sperm andegg, of sexual selection, of development in the womb and inchildhood that led to the specific adults in our group.

Now, out of all the accidents in the history of the universe,some of them are more productive of mutual information, moreproductive of regularities than others. The fluctuation that gaverise to our galaxy, for example, might not be considered veryimportant on a cosmic scale, but to everything in this galaxy it isof enormous significance that the galaxy came into being. Simi­larly, many events in human history represent branchings withhuge effects on the future history ofhumanity on the Earth.

Historians nowadays like to talk about Annie Oakley, thefamous female sharpshooter in Buffalo Bill eody's Wild WestShow, which travelled across Europe in 1889. One of the featuresofthe show was that Annie Oakley offered to shoot part of a cigarout of the mouth of a volunteer from the audience. Typically, noman volunteered for this dangerous job and her husband, himselfa famous marksman, would step forward with his cigar. AnnieOakleywould shoot the ash offher husband's cigar and the audi­ence would applaud. But in Berlin, in 1889, there was a volunteerfrom the audience - the Kaiser. He had been on the throne forjust one year when he volunteered to be the victim ofAnnie Oak­ley's shooting stunt. She was worried about her aim - she hadbeen drinking heavily the night before - but she had no choice.The Kaiser removed the band from his expensive Havana cigar,clipped off the end with his silver cigar cutter, put the cigar intohis mouth and lit it. Annie aimed at the end of it and shot off theash. She did not kill the Kaiser, but what if she had? Historywould probably have been quite different. The First World Warmight have been very different - indeed, it might never havehappened - and so on and so forth. Here we have an example ofa frozen accident, one that produces a great deal of future mutualinformation in a portion of the universe that is of interest.

We can now answer the question of why there is, in so manydomains of experience, a tendency- for entities of greater andgreater complexity to come into being as time goes on. The fun­damentallaws of nature, we have said, are very simple, includingthe initial condition of the universe, but those laws are probabilis­tic. So we have a branching tree with probabilities, with accidentsat the branchings. Some of these accidents - the frozen acci­dents - are more important than others. Now, as time goes on,more and more frozen accidents can accumulate, making possi­ble the emergence of more and more regularities. If theaccumulation of the results of frozen accidents outstrips the era­sure or disappearance of the results ofsuch accidents, then thingsof greater and greater complexity can" come into being as timegoes on. It is of course, not true that every individual thingbecomes more complex. Far from it; for instance, organisms andcivilisations die and become, naturally, much less complex in theprocess. But what we can say is that in many cases the envelope ofcomplexity keeps getting pushed out as time goes on, so that

20

more and more complex entities come into being.Now, the appearance of more and more complex entities as

time goes on is in no way incompatible with the famous secondlaw of thermodynamics, which states that the average disorder,the average entropy, of a closed system has a tendency to increasewith time. But that is average disorder - there is nothing to stopmechanisms of self-organisation from producing local order atthe expense of greater disorder elsewhere. We know of manymechanisms of self-organisation, for example gravitationalattraction, which has produced galaxies, stars, planets, rocks, etc.Likewise, low temperatures give rise to the beautiful, regularshapes of crystals or snowflakes.

Let me end by asking about the future. Will things of greaterand greater complexity keep on appearing in the universe? Well,we don't know for sure, but we can speculate about it. Many theo­retical physicists believe, although so far the experiments havenot proved it, that the proton will ultimately be found to beunstable. If so, then atomic nuclei are all unstable, with lifetimesperhaps something like 1035 years (that's a one with 35 zeros afterit - a very large number of years). After some such time, nucleiwould mostly be gone, and atoms and molecules would disap­pear too. Most of the regularities with which we are familiarwould disappear, and it may be that then entities of greater andgreater complexity would no longer keep appearing. In fact, theenvelope of complexity might start to shrink when most of thenuclei are gone.

However, that is not of immediate concern. We have manymore pressing worries.

(talk delivered to the symposium "Frontiers of Science" held in Coimbra,Portugal, 1999)

European Group for Optics

and Photonics (EGOP)

The Quantum Electronics and Optics Division of the Euro­pean Physical Society (QEOD of EPS) and the European

Optical Society (EOS) share a strong desire to establish oneunique voice to speak for the optical science and engineeringcommunity in Europe.

As a first step towards greater integration, the Prof. Dr. TheoTschudi (President of EOS) and Prof. Dr. Guenter Huber (Presi­dent of QEOD-EPS) signed an agreement in November 2001 tocreate a European Group for Optics and Photonics (EGOP), as acoordination mechanism between the two societies.

EGOP is concerned particularly with those topics that benefitfrom a close collaboration between physicists and optical engi­neers. The QEOD and EOS will use EGOP to coordinate theirrelevant activities in optics and photonics, and to represent thetwo societies in discussions with outside partners when bothsocieties wish to be represented as one. Especially, there is astrong wish of both societies to coordinate and collaborate inconferences. EGOP is an informal structure and has no conse­quence on the membership and structure of QEOD-EPS andEOS, or on their rules of operation.

europhysics news JANUARY/FEBRUARY 2002

Below is a list of EPS Europhysics Conferences, and EPS Sponsored Conferences. Euro­physics Conferences are organised by EPS Divisions and Groups. Sponsored

Conferences have been reviewed by experts in the field following application, and based oncriteria such as timeliness and topical coverage, are considered to merit EPS sponsorship.

2002 EUROPHYSICS CONFERENCES I

19th General Conference of the CondensedMatter Division of the European PhysicalSociety held jointly with CMMP 2002Condensed Matter and Materials Physics7-11 April 2002 the Physics Congress,Brighton, UKContact: Conferences Dept.The Institute of Physics,76 Portland Place, London W1B INTtel. +442074704800 tax +44 20 7470 4900email conferences@iop.orgweb http://physics.iop.org/IOP/confs/CMD19/

European Particle Accelerator ConferenceEPAC200203-07 June 2002 Paris, FranceCite de la Science, Centre des Congres de laVillette, FranceContact: Prof. J. Le DuffLAL Laboratoire de l'Accelerateur LineaireUniversite de Paris Sud, Bat. 34 F - 91898OrsayCedextel. +33 1 64468430 tax +33 1 6907 1499emailleduff@lal.in2p3.frMrs. Ch. Petit-Jean-GenazCERN - AC, CH - 1211 Geneva 23tel. +41 22 767 32 75 tax +41 22 767 94 60email Christine.petit-jean-genaz@cern.chweb http://epac.web.cern.ch/EPAC/

29th EPS Conference on Plasma Physicsand Controlled Fusion17-21 June 2002 Montreux, SwitzerlandContact: Dr. J.B. Lister or Dr. Y.R. MartinCRPP-EPFL,CH - 1015 Lausanne, Switzerlandtel. +41 21 693 3482 tax +4121 693 5176email eps2002@epfl..chweb http://crppwww.ep~.ch/eps2002

34th Conference of European Group ofAtomic Spectroscopy 2002 (EGAS 2002)9-12 July 2002 Sofia, BulgariaContact: Dr. K. Blagoev72 Tzarigradsko, 1784 Sofia, Bulgariatel. +5927144646 tax +592 9753226email kblagoeV@issp.bas.bg or34egas@issp.bas.bgweb http://www.issp.bas.bg/egas34

Synchroton Radiation in Polymer Science 1104-06 September 2002 University ofSheffield, UKContact: Professor A.J. RyanUniversity of Sheffield, Dept of Chemistry,Brookhill,UK - Sheffield S3 7HFtel. + 44 1142229409 tax + 44 1142229303email tony.ryan@shef.ac.uk

5th Liquid Matter Conference14-18 September 2002 University of

europhysics news JANUARY/FEBRUARY 2002

Konstanz, GermanyContact: Universitat Konstanz, FachbereichPhysikD - 78457 Konstanz, GermanyConference Chairman: Prof. Rudolf Kleintel. + 49 7531882955 tax + 49 753188 3157email rudolf.klein@uni-konstanz.deProf. Georg Marettel. +49 7531 884788 tax +49 7531883864emailliquids2002@uni-konstanz.deweb www.Liquids2002.de

2002 SPONSORED CONFERENCES

Second International Meeting onPhotodynamics10-16 February 2002 Havana, CubaContact: Prof. Jesus Rubayo SoneiraInstituto Superior de Ciencias y TecnologiaNuclearesAve. Salvator Allende y Luaces, Quinta de losMolinos, Habana 10600,A.P. 6163, CiudadHabana, Cubatel.+53 7 785018tax +537785018 or +537241188email jrs@rsrch.isctn.edu.cu

IUPAP International Conference onWomen in Physics06-09 March 2002 UNESCO Headquarters,Paris, FranceContact: IUPAP International Conferenceon Women in Physicsclo American Physical SocietyOne Physics Ellipse, College Park,MD 20740 USAtel. + 1 301 209 3269 tax + 1 301 2090865email beamon@aps.orgweb www.i£ufrgs.br/-barbosalconference.html

5th International Topical Meeting onIndustrial Radioisotope and RadiationMeasurement Applications (IRRMA-V)09-14 June 2002 Bologna, ItalyContact: Professor Jorge E. Fernandez(Chairman)University of Bologna Laboratory ofMontecuccolino-DIENCAvia dei Colli, 16, I - 40136 Bologna, Italytel. +390516441718 tax +39 0516441747email chairman@irrma.unibo.itweb http://www.irrma.unibo.itl

International Quantum ElectronicsConference collocatedwith the Conference on Lasers, Applicationsand Technologies - IQEC I LAT 200222-28 June 2002 Moscow, RussiaContact: Institute of Laser Physics SB RASProspect Lavrentyev, 13/3, RU - Novosibirsk630090, RussiaProf. Sergei N. Bagayevtel. + 7 3832 33 2489 tax + 7383233 2067email bagayeV@laser.nsc.ru

EPS MEETINGS LISTING

Dr. Vladirnir 1. Denisovtel.+7 3832 33 34 78 tax +7 3832 33 34 78email denisoV@laser.nsc.ruweb http://www.ilc.msu.suliqec/

Europhysical Conference on Defects inInsulating Materials (EURODIM 2002)30 June - 05 July 2002 Wroclaw, PolandContact: Professor Maria SuszynskaInstitute of Low Temperature and StructureResearchPolish Academy of Sciencesul. Okolna 2,PL - 50-950 Wroclaw, Polandtel. +48 71 343 50 21 tax +4871 2441029email suszyn@int.pan.wroc.plweb http://www.int.pan.wroc.pllks/konferencjeleurodirn20021eurodim2002.asp

International Conference on LaserProbing (LAP 2002)07-12 July 2002 Leuven, Flandres, BelgiumContact: LAP Conference SecretariatCelestijnenlaan 200 D,B- 3001 Leuven, Belgiumtel. + 32 163272 04 tax + 32 16327983emaillap2002@fys.ku1euven.ac.beweb http://www.fys.ku1euven.ac.be/vsmllap2002

International Conference on TheoreticalPhysicsTH-200222-26 July 2002 Paris - UNESCO, FranceContact: Prof. Daniel Iagolnitzertel. +331690881 15email iago@spht.saclay.cea.frProf. Jean Zinn-JustinteL +33 1 69087468email zinn@spht.saclay.ceaJrCEA-Saclay. Service de Physique TheoriqueF - 91191 Gif-sur-Yvette cedex, France

Conference on the Elementary Processesin Atomic Systems (CEPAS 2002)02-06 September 2002 Technical Universityof Gdansk, PolandContact: Brygida Mielewska ElzbietaPtasinska-DengaTechnical University of GdanskFaculty ofApplied Physics and Mathematicsul. Narutowicza 11,PL - 80-952 Gdansk, Polandtel. + 48 58 3471069,3471461 tax + 48583472821email cepas@mif.pg.gda.plweb http://www.mif.pg.gda.pllcepas2002

International School of Nuclear Physics,24th Course,"Quarks in Hadrons andNuclei"16-24 September 2002 Erice, ItalyContact: Prof. A. FaesslerUniversitat Thebingen, Institut flirTheoretische PhysikAuf der Morgenstelle 14, D-72076 Tiibingentel. + 49 707129 76 370 tax + 49 7071 29 5388email amand.faessler@uni-tuebingen.deweb http:/www.uni-tuebingen.de/erice/

21

REPORTS

The word from BrusselsTom Elsworth

This is the sixth article in the present series and a year haspassed. Have we made progress on Framework Programme

6? Yes we have as you will see below. Is thinking in Brussels mov­ing in a sensible direction? Yes again, I think. Is everything wellwith the world in that case? Not really, not only are the horsemenof the apocalypse loose, except from the narrowest science ori­ented point of view, but also there is fear of recession and afrisson of concern about how things will pan out with the Euro.

For myself, I take a positive view and this is of course colouredby my own interests and experience. For example, a couple ofweeks ago I attended two events in the European Week of Scienceand Technology. My company (Communque PR) was involved inorganising the events (called EuroPAWS) as part of a consortiumworking under the Framework Programme 5, "Raising PublicAwareness" programme. More information about the events canbe found at www.europaws.org or at www.alphagalileo.org or atwww.cordis.lu.

Suffice it to say for this epistle that the events were intended tohave two impacts, firstly to bring something professional, refresh­ing and new to the European Science and Technology Week(ESTW) and Raising PublicAwareness (RPA) generally. Secondlyand more importantly, they were directed at convincing writers,producers and broadcasters of TV drama that good science andtechnology is a viable, exciting and audience friendly topic. Wedid this by showing excerpts from real top quality TV dramamaterial (e.g. "Longitude" from Channel 4 in the UK) and alsopresenting live dramatisations of new scripts with a science bent.The main idea behind all this being that science needs access tothe immense communicating power of TV drama (includingsoaps because they obviously have the highest impact in terms ofaudience). We also feel that the easy approach to raising publicawareness - putting on some sort of amateur direct public con­tact event that touches a few thousand people (usually schoolkids because it is easy to get a good turn out) at most is far fromcost effective.

The EuroPAWS events, in particular the live renditions offuture TV scripts, were judged a success by all those involved andthe positive reaction received was such as to encourage the con­sortium to do more of the same in future years - so watch thisspace and ifyou are at all interested in this field please look at thewww sites listed above or contact me directly (see box)! This thenwas an example of a real move in the right direction.

Turning now to Framework Programme 6, the most recentdevelopment (14th November) is a vote in the European Parlia­ment. Gerard Caudron, the rapporteur presented reports fromthe Industry and Research Committee dealing with Euratom andFP6 (under the consultation procedure) and FP6 generally(under the co-decision procedure). The main point to note is thatthe proposed budget ofEuro 16,270B was endorsed (unlike theawful budget row for previous Framework Programmes). Sec­ondly, we have considered in these articles more than once thequestion of the so called "new instruments".The Caudron reportcontains some notes of concern about thesej in that they areuntried, but it generally accepts the logic of their application.However, Caudron proposes an additional instrument called,somewhat quaintly, the "stairway to excellence" essentially as an

22

entry level instrument for candidate countries, SMEs, newresearch institutes and small scale projects. This seems a mildproposal and indeed I would characterise the whole report inthat way.

The Euratom report was likewise on the whole, mild. Onfusion research however there was an historic eventj for the firsttime the Parliament voted for an increase in fusion funding, byEuro lOOM to Euro 800M. The Caudron report says "Parliamentagrees that controlled thermonuclear fusion is one of the longterm options for energy supplies in conditions of sustainabledevelopment" - hoorah! The Parliament is to be congratulatedon this sensible position.

The next question however, is how will the Commission andCouncil of Ministers react (it is the consultation process whichapplies so the decision lies with them in reality)? My own view forwhat it is worth, is that the time of fusion is coming and rapidly.All the signs are that UK Government is now a strong supporterand I should think France and Germany would be too. Indeedthe time scale attached to energy security concerns strongly indi­cates an acceleration of fusion research - perhaps to enable adecision, post ITER, to build a demonstration power station in 25years or so. Expect announcements on all this soon!

Calls for Proposals

Calls published to 16 November 2001

Promoting a User-Friendly Information Society

8th 1ST Call published on 16 November 2001Opening date: 16.11.2001Closing dates: variously 21sI or 28th February 2002

Quality ofLife and Management ofLivingResources

4th Call for Proposals for RTD actionsOpening date: 31.10.2001Closing date: 31.01.2002

Competitive and Sustainable Growth

Dedicated call Measurements and Testing, InfrastructuresOpening date:16.1O.2001Closing date: 15.02.2002

Research and Training in the field ofNuclear Energy

4th Call for Proposals for RT Actions under the Specific Pro­gramme for Research and Training (Euratom) in the Field ofNuclear Energy (1998 to 2002) Key Action 2; Nuclear Fission)

Call Identifier: NE-Fission Fourth CallOpening date: 16.10.2001Closing date: 21.01.2002

Open Call for Proposals for RT Actions under the Specific Pro­gramme for Research and Training (Euratom) in the Field ofNuclear Energy (1998 to 2002)

Call Identifier: NE Open 2Opening date: 16.10.2001Closing date: See evaluation cut-off dates in call text

Call for Proposals to extend Existing Contracts under the Spe­cific Programme for Research and Training (Euratom) in the

europhysics news JANUARY/FEBRUARY 2002

Field of Nuclear Energy (1998 to 2002) to include Partnersfrom the "Newly Associated States" (NAS) associated to theEuratom Programme

Call Identifier: NE Fission NASOpening date: 16.10.2001Closing date: 21.01.2002

Quality ofLife and Management ofLivingResourcesCompetitive and Sustainable GrowthEnergy, Environment and Sustainable Development

Joint call for proposals to support for the integration of"newlyassociated states"(NAS) in the European research area

Opening date: 20.09.2001Closing date: 31.01.2002

Confirming the international role ofCommunity research

Call for Proposal for Accompanying MeasuresOpening date: 18.09.2001Closing date: See Call text

Promotinga User-Friendly Information Society

An Initiative on 2.5-3G Mobile Applications and ServicesOpening date:04.09.2001Closing date: See Call text

Improving Human Research Potential and the Socio-economicKnowledge Base

TheArchimedesP~2001

Opening date: 04.09.2001Closing date: 15.03.2002

Competitive and Sustainable Growth

Call for proposals to extend existing contracts to include part­ners from the "NewlyAssociated States" (NAS)

Opening date: 01.09.2001Closing date: 13.12.2001

A summary of one year in BrusselsIt has been a year largely devoted to preparing future researchactivities and this work has yet to reach its climax. But the signsare I think, positive; Parliament and the Commission and Coun­cil seem in broad accord on the thrust of FP6 and the generalobjectives ofenhancing quality and pushing forward with initiat­ing the creation of a European Research Area to rival thecapabilities of the United States. There is a very long way to go ofcourse, on both FP6 in particular and ERA in general (I shallreally believe we have one when Europe has a single body asinfluential on the AAAs!). The current president of the ResearchCouncil (at the time ofwriting late in November 2001) Francois­Xavier de Donnea proclaims himself confident that the 10th

December meeting ofhis Council will" ...bring together the finalstrands needed for agreement on the details of the next Frame­work Programme...". We shall soon see whether the EUinstitutions have grown up sufficiently that the hiccups of previ­ous Framework programmes can really be avoided!

A happy 2002 to all readers ofEurophysics News.

europhysics news JANUARY/FEBRUARY 2002

REPORTS

CommunIque PR Is a wmmunic;:atjons consulting firmspecialrsing in supporting organisations in the sdence,engineering ana technelogy sector-s. Areas of work that can betal!kled in<:lude media relations, evenf management, video apdprint promotioNI mat!!Iial, public awareness activities, lobbYing if]BrlJs~sels or in relatia'n to EU linked activities ana strategic planningami integratia,n of intemal and external corpojate cammurii­eations. Public RelatioQs and Pu_blic Affairs.

Tom Elsworth, one af the partners- in Communique PR, hasprepared this artide (it reftects his own 'opihions on matters inBrussel~). Tom has experien<:e walking in the external relatians afmajor scien:ce oased organiSation'extending over 25 years and inloeatiens induding L.onaon, Brussels and Washington DC Recentcustomers Qf CGmmuniq~e PR include riPS, UK Atomic EnergyAutnorfty andth'E! C:ommlssion of the EU.

Tom can be <:ontacted a~:

(;ommuniClue PRBUrhsid~, Beggars Lane, tongwarthAbingden. Oxen. 0X13 SBl. England

tel/fax +44 to) 865 820 533 me.tJile f44 ~O) 7711 353427.e,maiJ tom.elsworln@barGlays.netweb www.cemmunlqllepr.com

Simplifying EuropeTwelve European countries have adopted the Euro as the commoncurrency. Fortunately, language and cultural differences remain.

expressed as an amount •••••**** with definite article

language one unit several units singular plural

DA I euro 100 euro euroen euroene

I cent 100 cent centen centene

DE I Euro lOOEuro der Euro dieEuro

I Cent 100 Cent derCent die Cent

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ES 1 euro 100 euros el euro los euros

I cent 100 cents el cent 10s cents

PR I euro 100 euros l'euro les euros

I cent 100 cents le cent les cents

IT I euro 100 euro l'euro glieuro

I cent 100 cent Hcent i cent

NL I euro 100 euro de euro deeurots

, I cent 100 cent decent de centen

PT I euro 100 euros o euro os euros

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23

REPORTS

An interview with Charles KleiberSwiss State Secretary for ScienceC. Rossel, Executive Secretary ofthe EPS and T. fung, President ofthe Swiss Physical Society.

I n a previous edition of EPN (32/3, May-June 2001), PhilippeBusquin the European Commissioner for Research was inter­

viewed and expressed his views on the issues facing EuropeanScience. In order to address the specific case of Switzerland, not amember of the EU, we asked a few questions to the Swiss StateSecretary for Science, Charles Kleiber. In addition to his function~ State Secretary, Dr. Charles Kleiber has also been director of

. the Swiss Science Agency since 1997. He was previously ChiefExecutive of the Association of the cantonal teaching hospitals inLausanne, Head of the Public Health and Planning Services andvisiting professor at the University of Lausanne.

The Swiss Science Agency that includes the Federal Office forEducation and Technology; the Swiss Space Organization and theCouncil of the Swiss Polytechnic Schools (ETH) has severalobjectives: Promote the excellence and efficiency of research andeducation, reinforce competitiveness of Switzerland and encour­age international scientific cooperation.

Mr. Kleiber, how do you see the integration and cooperation ofSwiss Science in Europe? What are the problems raised by the factthat Switzerland does not belong to the EU?

Good science is international. Swiss Science cannot be excellentalone, we need cooperation within international networks, inparticular with Europe for political and cultural reasons. WhileSwitzerland is partly isolated, it is not easy to have our ownnational policies and to run different bilateral policies with Euro­pean countries in parallel. This is a very complex relationship.In fact we enter a time ofa relationship that I call "menage a trois"between Science, Democracy and Economy that are getting moreand more intertwined. Science is and remains the pleasure ofknowledge with no limits but has to take into account the rules ofdemocracy and economy.

Within the European Research Community, it is often criticized thatmost national scientific communities do more actively collaboratewith the United States, than with their European partners. Is thisalso the case for Switzerland, and what is your opinion on this mat­ter?

Of course it is the case. Many Swiss scientists went to the USA orare part of the US science system. This is good for the interna­tionality of Swiss science. We have to pick up the best of theAmericat). model based on competition. We also have to shapenew ways of collaboration in Europe that are consistent with ourEuropean traditions and values.

What is your opinion on the 6th EU Framework Program?

This program is a necessary compromise between hundreds ofactors, with no clear shape yet. It is like an 'auberge espagnole',you take out what you put in. Up to now over 700 propositions ofchanges have been made. I really hope that this program will putemphasis on basic research in science, social science and human­ities.

24

Where do you see the strengths of Switzerland in Science in gener­al and in Physics in particular? Do you think that Switzerlandinvests enough in expenses for research and development with2.6% of its national growth product?

You are the scientists; the physicists and you know better wherewe are strong. Of course, there are several areas with traditionalstrength: for example, in high energy physics at CERN and moregenerally in condensed matter physics. Concerning the invest­ment, 2.6% is certainly not enough. Other countries invest more.Equipment is getting older, people leave the country. Ifwe do notincrease our investment in science, we will be in danger, becausein a small country like Switzerland the economy strongly relieson scientific achievements. To remain on the cutting edge and tokeep or attract the good scientists, we have to take the right deci­sions and invest accordingly. Small countries, in proportion, mustinvest more than big countries, which can count on mass effect.They also have to choose their priorities, what is always risky.

If we ~ad the same financial problem for Swiss science as Swissairrecently encountered would the government help in a similar man­ner?

No, clearly not. Swissair is a symbol of identification for the pop­ulation. This is not the case for Swiss research. We certainly needmore information campaigns to raise public awareness on sci­ence. The program Science et Cite with public events in all majorcities has been shaped for this purpose.

In the indicator for technology development published by theUNPD (United Nation Program for Development) in July 2001Switzerland ranks very well between Germany and Austria in termsof number of patents. Nevertheless none of the Swiss Research(enters appears in the list of large world centers for technologicalinnovation based on a study of the magazine "Wired': Why is it so?

This is indeed a problem. Scientific creativity and standards inour country are very high and in principle we should be betterable to transform knowledge into products. There are two rea­sons for this problem: the first one is cultural; the scientists haveto learn how to valorize their inventions. The second one issocial. With the existence of a centralized orga-nization for the valorization ofknowledge, the so-called Commissionfor Technology and Innovation (CTI),the Universities and the ETH did maybenot feel responsible enough for technol­ogy transfer. Now this has beenimproved with a new and clear situationas far as property rights are concerned.Once the newly created offices fortechnology transfer within univer­sities and research institutionsget more established, I expectSwiss Science to create moretechnological innovation.

europhysics news JANUARY/FEBRUARY 2002

I might add that for the precise example of th~WIRED study,there was also a technical problem: the indicators used in thestudy were not available for Switzerland.

What are your feelings about fundamental research? Do you thinkthat the links between industry and research in Switzerland arestrong enough?

Swiss firms invest more abroad. This means that they find betterconditions outside Switzerland. In my opinion the situation isimproving but we certainly have to work more on it. For exampleI believe that our country is a good place for investments in lifescience and we have to convince companies to do so. Highsalaries and social charges are not a major concern if investorsfind a high quality of services and a good cultural life. Firms arechanging their strategies by establishing new partnerships withuniversities. In some cases they even install their own researchgroups within the universities, taking advantage of a creative andstimulating environment.

As proposed by Philippe Busquin, Europe needs to have centers ofexcellence. On December 18,2000 the Swiss ministry of interioraffairs announced the creation of the first National Centres ofCom­petence in Research (NCCR) to promote scientific excellence inareas of strategic importance. Two of the projects are related tophysics: "Nanoscale science" and IlMaterials with Novel ElectronicProperties': What criteria were used for the final choice?

Out of 237 initial projects, the Swiss National Science Foundationretained 18 proposals and finally 14 have been financed. Threemore are to come. The attribution ofthese significant funds to basicresearch is of course a political decision. With two projects inphysics, I assume that the physicists are happy.

Over the past few years there has been a strong decrease of physicsstudents in the Universities and fewer go today into research. Fromyour point of view, what are the reasons and what can be done toreverse this tendency?There is indeed a phase of concentration in physics. For example,and contrary to other universities, the last figures from the ETHZshow stability or even a small rise of the number ofstudents, 30%in chemistry and 10% in all other sciences.

Is a migration of the students to the larger ETH schools not a dan­ger for the smaller faculties that might collapse by lack of students?

europhysics news JANUARY/FEBRUARY 2002

REPORTS

No, the smaller universities are certain to remain but you cannothave a strong and sustainable institution with only a couple ofprofessors and a handful of students. Are they strong enough tohave a faculty of science? It depends on the creativity of theirresearch teams and their international connections. Creativitythrives on debate but when you only have one of a few facultymembers and students, controversies are hard to entertain!Therefore smaller (or all?) universities will have to concentratetheir efforts on those disciplines where they are excellent. Thesupport of small universities is a matter of cost. It would only beproblematic ifone directly links the funding a faculty or universi­ty to the number of students.

There has been lately a strong promotion for life sciences andbiotechnologies as seen from the,marked refocusing of the FederalInstitutes ofTechnology.lsn't it a danger to over do it and weakenother sciences like physics, chemistry, electrical engineering orcomputer science?

Where is the balance? You have got two NCCR programs inphysics out of 14! We have to look where the core business of theindustry is and invest where we are strong. Basic sciences will bedeveloped, as seen by the transfer of the mathematics, physicsand chemistry departments from the University of Lausanne tothe EPFL. Switzerland is a good place for life sciences, with clus­ters of strength in Science, education, medicine and biotechindustry in Basel, Zurich and GenevalLausanne. The ongoingexpansion of life sciences is not directed against physics: the oldview of disciplinary kingdoms is outdated; interdisciplinary iswanted. In short, physicists will increasingly have to deal with lifescientists, as already exemplified by the recently inauguratedSwiss Light Source.

You have organized the program "Science et Cite" to better commu­nicate the image of Science to the public. Key manifestations tookplace in different Swiss Cities. The press and the public respondedvery well. What are your plans for the future in this field? Do youplan any activity at the Swiss National Exposition EXP002?

I would like to say that Science et Cite is part of our science poli­cy. This national manifestation has been very successful andtakes place every 2 or 3 years, the next one will be in 2004. Weorganize also so-called scientific cafes to discuss new topics orhave the questions of the public answered by specialists. Such anevent is planned at Expo02. Next year the theme of "humanembryos in research" will also be addressed. Another project is tobuild the future Houses of Science et Cite in the Cantons ofZurich, Ticino and Vaud so to decentralize our activities. Themain issue is to bring knowledge out of the universities into thestreet by creating open debates on radio, TV; etc. The public,being the taxpayer, has to be convinced that science is importantfor the future of our society. If scientists do not succeed here,investment into science will further decline. Moreover, the tax­payer has to be convinced that science is not only a problem forspecialists; he too, has his word to say.

The European Physical Society (EPS) and National Physical Societiesrepresent a large body of European physicists. How do you see theirrole in influencing science politics and promoting the image ofphysics?

To my view, learned societies are needed to disseminate the scien­tific culture. They should also participate to political debates anddecisions. As you say, all national institutions like the SPS and theSwiss Academy of Science should raise public awareness and alsoestablish a better link between scientists and politicians. Science

25

REPORTS

education at school could also start earlier to raise a largercuriosity among youngsters. Let me add that as science policy isconcerned, this is too important to be left solely in the hands ofscientific lobbies or only to politics, for that matter. Science policyis a collective endeavor.

At the World Congress of Physical Societies in December 2000 inBerlin, the EPS has launched the project "2005, World Year ofPhysics" to promote the image of Physics. This choice has beenmainly motivated by the wish to commemorate the famous publi­cations of Albert Einstein in 1905, its "miraculous year~ Severalmanifustations are planned in Switzerland.What are your visions inthis respect?I shall be very happy to help with this project and would well seethe Foundation Science et Cite involved in an action. Why not ona topic like "Physics and the Citizens"? The impact of physics onthe society since 1905 has been enormous, and Einstein is cer­tainly the most popular and best-known scientist.

The science lecture:theatre in the round?Denis Weaire, Trinity College, University ofDublin, Ireland

Switzerland is a Federation of 'Cantons~ which are running theirUniversities with independent science policies. To some extent,your role as State Secretary for Science is to orchestrate the actionsof independent bodies.What have been your good and bad experi­ences on this job?My role is first to create the good conditions for the developmentof science in our country so that young scientists feel that theyhave a future. This has to be done in collaboration with the can­tons. One ofmy good experiences on the job is that the scientificcooperation between Cantons and Confederation works well,and might even be the best among all. The intensification of thiscooperation follows a reform strategy started in 2000 and whichshould extend to 2007 with a new constitutional article. This isnot enough, we have to reform, not suppress, the small universi­ties and help them to reinvent themselves. They are the actors in acompetitive world, where funding, like that provided by theNCCR program is attributed based on quality and scientificmerit. Bern, 23 October 2001

balconies that seem to overhang the stage. Aristocratic patronswho arrived late in the best of these could ask for the play to berestarted.

I f you work at a university and want to provoke a really goodargument, broach the question of the ideal shape of the lecture

theatre. Opinions vary, and they are rarely understated.There are two poles ofdisagreement. One the

one hand there is the steeply raked, overbearingform of the traditional amphitheatre: the semi­circular bowl where Faraday stood at the RoyalInstitution or the chemistry theatre of the oldpolytechnic university in Lisbon. At the otherextreme is the more rectangular and shallowspace of an auditorium or cinema.

In the planning committees of universities,battle is joined between the two factions. Sur­prisingly it is the scientists who favour the moreantique and intimate design. Points at issue willinclude acoustics and efficiency (rectanglescome cheap) but perhaps most importantly the"feer' of the theatre. The experience of bothspeaker and audience is quite different in thetwo cases.

In the flat design, the lecturer climbs to alectern as a priest to his pulpit in a medievalcathedral, to talk down to his congregation.Received wisdom is to be dispensed from abook to the multitude by a privileged minorityof the learned. Is not the arts lecturer, readingwith such exactitude from a meticulously prepared script (thesame as last year's, and the year before) in that position?

The scientist comes to his flock with uncertain and provision­al conclusions about the workings of the world. Like one ofShakespeare's modest prologues, this is but a poor player, humblyinviting the attention of the audience to dissect a piece of nature'splan"within the girdle of these walls". The wonderful Globe The­atre, now reconstructed, places many of its customers in high

26

Sir Robert Ball at thebench in the RoyalInstitution, in the earlyyears of the 20th century.

In the old science lecture theatres thatgive the audience such a privileged posi­tion, the ghosts of great masters of thedemonstration lecture prowl about thebench. Their art, which had its heydayin the 19th century, is now largelydefunct. But the physics lecturer stilldoes well to dance around upon hisstage, layout some props upon thebench and call out from time to time:"Hey, look at this!" The convergentfocus of attention of the awakenedonlookers gives a dramatic punch to theexperience. It can stick in the mind fordecades. A good coup de theatre isworth ten thousand words. If Hamlethad not held up the skull, who wouldremember Yorick?

But perhaps you do not agree? Youprefer the lectern to the bench? And dis­ciples at your feet to inquisitive eyesranged about and above you? Ab well,wise was that person that first said: "Anacademic is one who thinks otherwise?'

Do you have any examples of good andbad practice in theatre design, orestablished guidelines? If so, send themto Europhysics News.

europhysics news JANUARY/FEBRUARY 2002

ACTIVITIES

East-West collaboration in nuclear scienceWolfram von Oertzen, Chairman of the NPDHahn-Meitner-Institut Berlin, 14109 Berlin, Germany

.............................................................................................................................................................................

The Sandanski-2 meeting on East-West collaborations inNuclear Science was held in May 2001 in the town of San­

danski (Bulgaria), about 6 years after the first meeting of thiskind with 115 scientists from 17 European countries, the USA,Japan and the Joint Institute for Nuclear Research in Dubna par­ticipating in the meeting. The scientific programme included 66oral contributions. This meeting has provided the chance to lookat the recent progress in the field of nuclear science. 2001 alsomarked the lO-year period, over which substantial political andeconomic changes have taken place in Eastern Europe. Thesechanges have had a decisive impact on the scientific communityin these countries, because the support for basic and applied sci­ence has decreased dramatically due to the collapse of theireconomic systems. Nevertheless educational institutions in East­ern Europe have continued to attract motivated young studentsand have produced well-trained young scientists. It should bealso noted that, in spite of the difficult economic situation in theEast, there are still good resources - experimental installations,technical and scientific manpower, and a well trained humanintellectual reserve. At the present meeting the excellent resultsfrom this region were presented. Evidently, the conditions vary inthe different Eastern European countries, and they differ stronglyfrom one institute or laboratory to another. Improving theirworking conditions is not easy. This statement holds true espe­cially for university laboratories and smaller institutes. Everyoneis aware that the future working conditions may become ratherunattractive, which in turn is likely to discourage the next gener­ation of students to embark on the study of science.

Collaborations in nuclear science existed in many fields beforeand at the Sandanski-2 meeting it was demonstrated that scien­tific contacts have been developed considerably in the last 5years.Manynational and European institutions, having realised the dif­ficult situation of scientists in the East, have set up supportprogrammes for the funding of local activities for scientists intheir Eastern institutions (e.g. The Soros Foundation), or moreextensively to fund collaborations between Eastern and Westernscientists (by NATO Science, INTAS, WTZ-Germany; CNRS­France, INFN-Italy; etc.). Many highly experienced scientistsworking in basic nuclear science now spend time working in

Western Europe, the United States and in Japan. It cannot beoverlooked that brain drain from the poorer Eastern Europeancountries is a real problem. These people are of course very wel­come in Western institutions, however, in the mid-term a collapseof the scientific community in the East can be anticipated. On theother hand, we must admit that the situation in the West is alsodisturbing. There, few young people adopt a career in physics,and many of those who do go to industry.

The EPS and the Nuclear Physics Board therefore have createdaction committees and "task forces" studying issues ofEast-Westcollaboration. At the Sandanski-2 meeting the majority of thelarge collaborations were present. The scientific program wasorganised to cover the following major fields ofbasic science:

•Nuclear reactions at low and intermediate energies• Radioactive beams and exotic nuclei• Heavy and super-heavy nuclei• Nuclear spectroscopy• Fundamental aspects in nuclear physics•Accelerator applications of nuclear physics• Public awareness ofnuclear science

Although this list of themes does not cover all collaborations, thesubjects illustrate the main directions of research in basic nuclearscience, which will also play a major role in the future. With thisselection, the strength ofEuropean nuclear science has been made .visible, but also lines of research for the further development canbe defined on the' basis of the very successful work being per­formed in strong East-West collaborations. The futuredevelopment of these fields is covered in the separate scientificsummaries of the conference (www.sandanski.ruls_summ.html).The high level of research done in these collaborations is docu­mented in the complete slide report to be found on the web-site.Their quality is reflected in the fact that the results presented alsoappear in the first ranks of international research conferences.The contributions of the partner institutions and scientists fromthe Eastern European countries are very important and are welldocumented in the corresponding presentations.

These presentations show the impact of several very successfulnational (mostly bilateral) programmes for support of research

europhysics news JANUARY/FEBRUARY 2002 27

ACTIVITIES

in collaborations with scientists from Eastern European researchinstitutions. These have played a major role in stabilising the sci­entific communities in the East. There are also recenttrans-national European programmes directed to support East­West collaborations. Programmes such as INTAS (www.intas.be).and NATO Science (www.nato.int/science) have been supportingresearch in nuclear science for the past ten years. It is understand­able that this support has been only a part of the total resourcesneeded for any investigation. However, the grants given withinthese programmes have been of great moral importance for theparticipants. They have been a way to make specific investiga­tions more visible, and have highlighted their importance. Theyhave helped to give this research a higher priority in the respec­tive home institutes, etc.

The documentation of the excellence of the research presentedat the Sandanski-2 meeting is not a reason to rest on our laurels.It has to be taken as a basis and a signal to make all efforts to co­ordinate and support the future activities on a European scale soas to prevent a possible collapse of the scientific communities inthe Eastern countries. This gains importance through the pend­ing entries ofmany Eastern countries into the European Union.

Scientific excellence in Europe has been achieved with a largecontribution by the scientists from Eastern Europe. Europeanscience needs the scientists from these countries as strong part-

European Journal of PhysicsAlastair I.M. Rae, Honorary Editor, European Journal ofPhysics

Physicists working in Universities and other higher-educationinstitutions world wide generally spend a similar fraction of

their time teaching physics as they do conducting research. As aresult, many valuable insights and new ways ofunderstanding aredeveloped. From the student point of view, the success of theirintroduction to university level physics often determines not onlytheir academic commitment to physics but also their futurecareer. It is therefore important that the teaching of physics atuniversity level be treated as a professional skill that needs rein­forcement and recognition. The European Journal of Physicsaims to assist and stimulate the teaching ofphysics in universitiesand to emphasise its importance for the successful long-termfuture of undergraduate physics, by publishing relevant papersand encouraging discussion.

The European Journal Physics is a journal of the EuropeanPhysical Society, which has been published by the UK. Instituteof Physics for over 21 years, its papers covering a wide spectrumof physics. The Editorial Board is drawn from universitiesthroughout Europe and includes representatives ofboth the EPSand the lOP. The journal's main focus is on topics that are ofpar­ticular interest and usefor teachers ofundergraduates and aimedat enriching their understanding of new and developing fields ofphysics. Papers featuring developments in the teaching of exper­imental physics are often of particular interest. Also ofprimaryimportance are papers covering the historical, social and techno­logical implications of physics in a wider context. Discussion ofthe theory and practice of teaching physics is also encouraged,along with contributions on education policies and their imple­mentation.

The European Journal ofPhysics has, over the years, publishedspecial sections with papers concentrating on particular topics.

28

ners in the future. Thus another very important conclusion fromthe Sandanski-2 meeting is obvious, that these collaborationsimprove the use of the available European infrastructureresources in a very effective way. The national and Europeaninstitutions have to therefore increase their funding of collabora­tions with Eastern Europe, existing successful collaborationshave to be further developed and, new ones must be createdaccording to the needs of science. This is also essential to achievea balance in Europe between East and West.

As another possible conclusion from the Sandanski-2 meet­ing, we forward the recommendation to create Europeanstructures for the support of scientists in their Eastern homeinstitutions in such a way that they can return and continue towork at home in conditions which will allow them to collaboratein European projects and to attract young people into their homeinstitutions.

East-West Coordination meeting on Nuclear Science was a EurophysicsConference held in Sandanski (Bulgaria) from 5 - 9 May 2001. TheConference was organised by: EPS, Nuclear Physics Board; Joint Institutefor Nuclear Research, Dubna; Bulgarian Academy of Sciences -Institutefor Nuclear Research and Nuclear; Energy, Sofia; The Committee ofPeaceful Use of Atomic Energy, Bulgaria.

These include "Unsolved problemsin physics"; "The electron: discov­eryand consequences"; "Quantumphysics in solids" and "The Life andwork of Hendrik Casimir". A spe­cial feature on EnvironmentalPhysics is planned for 2002.

A glance at any recent issue ofthejournal shows that the authorship ofthe papers is truly international, andthis is reflected in a reader circula­tion that spans not only the majorphysics departments of Europe but also North America and therest of the world. A full electronic version of the journal plus tenyears' archive is available at no extra cost to all institutional sub­scribers, thus increasing the level of exposure for paperspublished in the journal. The potential readership ofthe journalhas also been doubled by the Institute of Physics Publishing'smany consortia agreements (including four national site licens­es) that give electronic access to Institutions that do not haveprint subscriptions.

The Editorial Board ofEuropean Journal ofPhysics would liketo encourage members of the European Physical Society with aninvolvement in educational matters to contribute their papers forpublication. All papers are peer reviewed and the journal isabstracted in ISI (SCIE; Research Alert and Current Contents:CC/PC&ES).

For further information on submitting your work go to theonline version of our Notes for Authors at www.iop.org/Jour­nals/nfa or the European Journal of Physics page atwww.iop.org/journals/ejp

europhysics news JANUARY/FEBRUARY 2002

tUWS FROM EPS

noticeboard

EPS QEOD Prizes............................................................Nominations are now sought for the following prizes

• EPS Quantum Electronics and Optics Prize, sponsored by NKT, for outstandingcontributions to quantum electronics and optics. One prize is awarded for fundamentalaspects, one for applied aspects.

• EPS Fresnel Prize, for outstanding contributions to quantum electronics and opticsfrom younger scientists, for work performed before the age of 35.

Details of the nomination procedure, which must be followed, will be given on the EPSweb page www.eps.org. Deadline for receipt of applications at the EPS office is March 28,2002 for both prizes.The Awards will be announced at the IQEC 2002, meeting in Moscow,June 22 - 28, 2002.

EGAS 34 conference.........•..................................................

Inmemoriam......................•..........On 14 December 2001 Prof. Eduard Nagaev diedunexpectedly. Until the last moment he was fullof energy and defended his ideas eagerly. Hewas born in Penza (Russia) in 1934 andgraduated at the Moscow State University in19S6. For almost 30 years he was Head oflaboratory at the Institute of Current Sources(Moscow), and during last decade he worked inthe Institute for High Pressure Physics andInstitute of Radioengineering and Electronics ofthe Russian Academy of Sciences as the Headscientific researcher. Among many Distinctionsand Honours he was USSR State Prize in 1984.During his wide scientific career he maderelevant contributions. One of the mostimportant was the developing of the theory of'spin polarons: He was a charismatic person andthe scientific community in the field ofmagnetic semiconductors and magnetic oxideswill miss him.

Prof. M.R.lbarraChairman ofthe Magnetism SectionCMD Division of the EPS

Workshop........••...............•The Wojciech Paszkowicz Institute ofPhysics will organize a Workshop onNew Methods of Low DimensionalStructures Characterization:VUV and X­ray Free Electron Lasers from June 1S- 17,2002, in Ustrofi-Jaszowiec, Poland.Since the first meeting, in 1992, theISSRNS is organized as a biennial event.It is a traditional forum for discussingfundamental issues of application ofthe synchrotron radiation and relatedmethods in natural science (physics,chemistry, materials science, molecularbiology, biomedicine). The scientificprogramme of the School includesinvited general lectures, postersessions and panel discussions. Thedeadline for submission of abstracts ofthe other contributed papers is 15March 2002. For more information,please visit the workshop's site athttp://info.ifpan.edu.pllceldis/wpS/

"ItVIPllB:1WA1l't ~I002:

Elections to the Board of the EPS-IGA.•....•....•..............•....................................•..The Statutes of the European Physical Society Interdivisional Group on Accelerators stipulate thatone third of the members of the Elected Board has to be renewed every two years. Nominationsmust be supported by 3 Members of the Group. Members are elected for 6 years (3 conferences).Six vacancies are announced herewith. Nominations should be made on the appropriate formavailable from the Budapest Secretariat, together with a short c.v. and description of the activitiesofthe candidate, should be addressed to M. Lazar, Nador Utca 7, H10S1 Budapest, Hungary

The deadline for receipt of nominations is: 8 March 2002. The resulting list of candidates andballot papers will be mailed to EPS-IGA Members who will be invited to vote by the deadline of 26April 2002. Newly elected Members of the Board of the EPS-IGA will be notified of the result of theelection in writing by mid-May 2002.

Elections to the Board of the NPD..•.........................................................The Board of the EPS Nuclear Physics Division is organising elections to replace outgoingmembers. Three vacancies are announced herewith. Nominations must contain a shortc.v. and a statement from the candidate, and should be addressed to M. Lazar, Nador Utca7, H1051 Budapest, Hungary. The deadline for receipt of nominations is: 28 February 2002.The resulting list of candidates and ballot papers will be mailed to EPS NPD Members whowill be invited to vote, if necessary by the deadline of 30 April 2002. Newly elected Membersof the Board of the will be notified of the result of the election in writing by mid-May 2002.

NEWS AND VIEWS

P.A. Muller, Faculty ofPhysics and Astronomy, Utrecht University,The Netherlands

gallery makes fine leasurely reading, because Pais has managed tofind a balance between the detached historian of physics and thepassionate physicist he never ceased to be. Admittedly, in mostportraits Pais is prominently present too. But this goyem does notdare to deny him that right.

The Editors of In Situ Real-Time Characterization of ThinFilms, Orlando Auciello and the late AIan R. Krauss - both

established Senior Scientists at the Argonne National Laboratory,Argonne, Illinois - have successfully selected fifteen knownexperts in the field of in situ real-time monitoring and analysis ofevolving growth and concurrent surface and iterface phenomenaof thin films for providing eight (two of which strengthened bytheir own participation) extensive, thorough, didactic, andresearch - illuminating Contributed Chapters covering attestedmethods for on the spot dynamic characterisation oftechnologi­cally and application-wise important epitaxial materials inseveral different environments.

In sequence, Time ofFlight Ion Scattering and Recoil Spectro­scopies (TOF - ISARS), Reflection High Energy Electron Diffrac­tion (RHEED), Ellipsometry, Reflectance Spectroscopies andTransmission Electron as well as Atomic Force Microscopy (TEM& AFM), LASER Reflectance Interferometry (LRI),X-Ray Reflec­tivity (XRR), Curvature - Based Techniques (especially theMultibeam Optical Stress Sensor - MOSS - LASER Deflectome­try Method), and Photo-Electron Emission Microscopy (PEEM)are the in situ real-time characterisation approaches laboriouslystudied, each enriched with an admirably and fruitfully vast Ref­erence alphabetical Literature.

The Subject of direct dynamic analytical characterisation ofthin films whilst being grown lies truly in the forefront of theneeds, the interests, and the ongoing research of Solid State andadvanced Optoelectronic Devices Science and Engineering; assuch it places the Book at the priority level of Library updatingfor the related University, Research Centre, and Dedicated HighTechnology Industry Working Groups - despite its unavoidablenot being all-inclusive:

The characterisation techniques focused on in the Book havebeen preferred on the basis on the one hand of their functionali­ty in vacuum and in the presence of ambient gases, eitherresulting from the deposition process or serving as a requirementfor the production of the desired chemical phase, and on theother of their employing sufficiently compact and non-luxuri­ously expensive instrumentation, thus permitting incorporation

europhysics news JANUARY/FEBRUARY 2002'

lu Sllll Real-Tltne( ha raLterlzar ion. . .,

~ 'I' Orlando Auciello &Alan R. Krauss, John Wiley & SortS, 2001266pages +xiv ,~~~----~'~',"~~~.'.~~'~,._..~~.j

In Situ Real-TimeCharacterizationof Thin Films

Abraham PaisOxford University Press, 2000;)t·;,~j;:r·

487pages i,Jlll:/1:.~.,.,~_'V..=.:'_.",,=,-,.,,-_.=~_-",,,,,~,,,,,,,,,,,,,,,,,,~-,,,._.=-_. ':";.:. ..\";,." -~'.

The Genius of ScienceAportrait gallery oftwentieth-century physicists

30

BOOK REVIEWS

The late Abraham Pais (1918-2000) has led an extraordinaryfruitful life, filled with history, physics and history ofphysics.

The Genuis ofScience is, and will remain, his last fruit and, apartfrom Pais' autobiography A Tale of Two Continents (1997), themost personal one. Pais paints portraits of eminent physicistsand of one universal genius (Von Neumann) of the 20th century,all of whom he came to know personally; some of them becameintimate friends (Bohr, Einstein, Jost, Uhlenbeck). Some of these"microbiographies", as Pais calls them, are superficially sketchy,such as the ones of Weisskopf, Yang and Lee (they occupy a fewpages only). Others display more depth and are at times moving,such as the ones of Bohr, Einstein, Dirac, Kramers and Uhlen­beck, who was Pais' teacher in Utrecht before Pais went intohiding during the war. Needless to say there is a lot of history ofelementary particle physics too scattered over these pages, thebranch of physics Pais contributed too for over a period of abouttwenty years, after he emigrated to the USA.

Occasionally the detached historian in Pais takes over, such aswhen he severely criticises Max Born's claim, made in his Nobellecture of 1954, that Einstein's photon hypothesis guided him tohis famous probabilistic interpretation of the quantum-mechan­ical wave-function. But most of the time Pais never forgets tomake clear that most of these brilliant physicists were his bud­dies. Pais gladly spills over autobiographic morsels on hismicrobiographies whenever he deems it appropriate.

One cannot help noticing that of the seventeen portraitedmen, thirteen are Jewish: Bohr, Born, Einstein, Feigenbaum, Jost,Klein, Von Neumann, Pauli, Rabi, Serber, Uhlenbeck, Wiesskopfand Wigner, the non-Jews being Dirac, Kramers, and the China­men Lee and Yang. I personally cannot help noticing that in theprevious century the Jewish people have suffered as well asexcelled in such an extraordinary disproportion. It seems as if inthe past century theoretical physics was an almost entirely Jewishenterprise - I mention that Weinberg and Witten are not evenamong the portraited physicists, but also portraits of Oppen­heimer, Feynman and Schwinger are absent, all three men whomPais knew. In particular a portrait of Oppenheimer, with whomPais led the Insitute of Advanced Studies in Princeton after thewar, is felt as a sad ommision, because together with Heisenberg(understandably not portraited) Oppenheimer is the most tragicfigure of 20 th century physics. In comparison to Heisenberg,Oppenheimer stands out as a morally superior being, but where­as Heisenberg never encountered any serious obstacle in hisprofessional career before, during and after the war, Oppen­heimer was shamelessly shattered by the government of the USAduring the McCarthy period. Despite this omission, Pais' portrait

of its as a dedicated analytic tool within a thin film epitaxialdeposition chamber.

The Volume itself is aestetically beautiful and , apart from asmall percentage (including those on the front cover) of itssketches being hurriedly drawn, is supported by numerous clearand exact graphs and several genuinely interesting diffraction,dark field, and electron microscopy images; the appearance of aliterally negligible amount of grammatical errors not at allimpeding the ease and enticement of reading and learning.

The Reviewer's enthusiasm for both the mentally pleasant andscientifically rigorous minuteness of the wealth of informationcompiled and the motivating justification of effective applicabili­ty produced, for all characterisation methods outlinedthroughout the Book, has been admittedly even more heightenedby Chapters 3 on Ellipsometry by Eugene A. Irene of the Univer­sity of North Carolina and 8 on Photoelectron EmissionMicroscopy by Martin E. Kordesch at Ohio University.

Professor Emmanuel A. Anagnostakis, Hellenic Army Academy,Hellenic Centre for the Study ofOptoelectronics, Athens, Greece

Cl (It' .1IIJ /1 \ ((All),' r Chaos and Harmony

Perspectives on ScientificRevolutions of theTwentieth Century

Trinh Xuan Thuan IOxford University Press, 2001 IP14+366pp.+70figs. !

: Trans1atedftPmFrench byAxelReisinger l.J

The book is about the main developments of science, basicallyof physics, during the 20 century and about their reflections

upon the philosophical understanding of the world. Both the titleand the subtitle are quite pleasing and raise high expectations.The contents, the subject index, the glossary, the well chosenillustrations and even the number of pages give the first impres­sion that the book meets the challenge to comprehensibly presentmodern science to the layman. In fact this is what the authorstates in the Foreword and his promise is readily supported bythe observation that there is more poetry than mathematics.

The book offers a rich variety of topics: from big bang, blackholes and wormholes to quarks and superstrings reaching up tothe mind-body problem, the self-referential systems and Goedel'stheorem. All this is wrapped accurately up in the dichotomies ofchance and necessity, chaos and harmony, creativity and conser­vatism, holism and reductionism, yin and yang.

The book is a challenge to interdisciplinarians, to philosophersand historians of science. They will be stimulated to revealnumerous lapses and discrepancies. In most cases these are quitesubtle which makes them even more risky for the layman. Thebook resembles a collage, or a parquette (to keep to the Frenchaccent of the translation) in which most of the pieces seem to beall right but their arrangement is rather awkward.A few extracts to illustrate this (all italics are mine).The "electrons may have left the electron gun as particles, butthey have turned to waves before reaching the slits" (p. 211)."Integers are not a product of our mind" (p. 314)... "why do

europhysics news JANUARY/FEBRUARY 2002

NEWS AND VIEWS

abstract entities forged in the minds ofmathematicians..:' (p.322)."The behavior of a collection ofelectrons is not haphazard but isperfectly well determined by the laws ofprobability" (p.329).Let the potential reader volunteer to make out this: "Even thoughwe cannot predict the weather a month from now, we have everyreason to expect that, for a long time to come, the Sun will riseevery morning and spring will return every year to reawakenNature and signal trees to bloom. Chaos is thus a powerful ally toquantum indeterminism in liberating matter from its determin­istic shackles:' (p.330).Forgive me, Shakespeare, for paraphrasing your lovely Sonnet116:

If this be errorless, and upon me provd,I never writ, nor no man ever read.

Michael BushevInstitute ofSolid State Physics, Bulgarian Academy ofScience

Books for review

From Nonlinearity to CoherenceDixon,Tuszynski, C1arksonOxford

Experimental Techniques in Condensed Matter Physics at LowTemperaturesR. C. Richardson, E. N. SmithAddison Wesley (Advanced Book Classics)

Introductory Nuclear PhysicsHodgson, Gadioii, Gadioli-ErbaOxford

Large Facilities in PhysicsJ. Schopper, M. JacobWorld Scientific

Neutron and Solid State PhysicsL. Dobrzynskl, K. BllnowsklEllls Horwood Series

Numerical Simulations in AstrophyslcsFranco, Lizano, Agullar, DaltabuitCambridge

Philosophical Reflections and SynthesesE.P.WignerSpringer Verlag

Physically Speaking. Adictionary of quotations on physics andastronomyc.c. Gaither, A.E. Cavazos·GaitherlOP Publishing

If you are interested in reviewing one of the above books, or inreceiving books for review In general, please send us name, andcontact co-ordinates, along with the your field(s) of specialisationto:

Book Reviews, EPS SecretariatBP 2136, 68060 Mulhouse Cedex, France

31

NEWS AND VIEWS

Letters.......••....•..............................................................................•........•..................In his letter published in EPN 32/5, Dr. R. Joern S. Harry ques­tions whether CO2 emissions associated to the whole nuclearfuel cycle, from ore extraction to waste disposal, are as low asexpected. He refers to an article (http://home.trouweb.nl/storm­smith) in which "the authors claim that in the end nuclear emitsabout as much CO2 as the burning of natural gas for an equiva­lent amount of electricity production" . If this were indeedfound to be the case, nuclear power would hardly be worth­while!

Three independent studies quoted below conclude, on thecontrary, that CO2 emissions associated to nuclear power, con­sidering the whole cycle, are quite low, comparable to those ofhydroelectricity:

In Sweden, a Vattenfall study entitled "Certified Environmen­tal Product Declaration of Electricity from the Nuclear PowerPlant at Forsmark" (http://www.environdec.com) finds 2.90g/KWh where the whole cycle is considered, and the quantitymeasured is the Global Warming Potential (green house gases),given in CO2 equivalents. This quantity actually breaks up into:

Finally, according to the work in progress at ISN (Institut desSciences Nucleaires de Grenoble) and elsewhere, there are goodgrounds to claim that converter and/or breeder reactors,because they convert essentially 100% ofthe Uranium or Thori­um fuel, would yield a considerably improved energy balance,thus further reducing greenhouse gas emissions per unit energyproduced. In our view, it is only with such converters (or breed­ers), based on the Uranium or, better, the Thorium cycle, that itwill be possible to justify classifying nuclear energy as sustain­able. Meanwhile, during the time needed to design and testthese new reactors, and develop or improve other environmen­tally clean energy production technologies, we feel that PWRscan fill the gap and help reduce greenhouse gas emissions to theatmosphere, as stated in our paper "Global Warming or NuclearWaste - Which Do We Want» published in EPN 32/2.

H. Nifenecker and E. Huffer

Energy source g/kWh C02 (approx)

Hydro 3

Wind 5.5

Nuclear 6

Solar (PV) 50

Gas combined cycle 450

Coal 980

A paper entitled "Energy Analysis of Power Systems"(http://www.uic.com.aulnip57.htm). by the Uranium Informa­tion Centre Ltd. (UIe) finds somewhat larger numbers: forFrance, where enrichment is done by diffusion but most of theelectricity comes from nuclear plants, the greenhouse contribu­tion for nuclear power is found to be less than 20 g/kWh. Asupplement to this paper discusses the "stormsmith" paper atsome length expressing strong disagreement with its content.One of the problems with the "stormsmith" paper is that itassumes all the electricity used in the nuclear fuel cycle comesfrom fossil fuels. Other problems are underestimated plant lifeduration and overestimated pre production greenhouse gasemissions and post production waste related energy demands.

In a paper entitled "Bois, charbon, petrole, gaz, nucleaire etautres, m~me probl~mes?" which could translate to: "Wood,coal, oil, gas, nuclear and others, same problems?" published in"La Jaune et la Rouge» N° 555 (May 2000), Jean Pierre Bourdier,Director of environment at EdF, gives 6g/kWh C02 emissionsfor the whole nuclear fuel cycle in France.

For a comparison of greenhouse gas emissions related to thewhole cycle for various energy sources, we would like to quoteVattenfallnumbers (data take from the UIC paper):

Pre-nuclear Production Phase (Pre-NPP)Nuclear Production Phase (NPP)Post-Production Phase (Post-PP)

2.17g1kWh0.556g1kWh0.178 g1kWh

Acknowledgments

Martin C.E. Huber, the Editor of the Special Issue on 'Physicsand the Universe' would like to express his thanks to his col­leagues. He was able to rely on the expert advice of the Board ofthe Joint Astrophysics Division, as well as on the guidance by theEPN astronomy correspondent, Frank Israel. He is deeplyindebted to them and, likewise, to the authors of the individualarticles, who all provided their manuscripts in time and at therequested length.

M.C.E. Huber, 65, has worked in laboratory astrophysics andextreme-ultraviolet solar spectroscopy. He was Head of ESXsSpace Science Department, and currently spends most of histime in the International Space Science Institute (ISSI, Bern)and the Harvard-Smithsonian Center for Astrophysics in Cam­bridge, Mass.

EPN would also like to take this opportunity to publish some of Ithe biographical details omitted from the last issue.

Luigi Piro is senior researcher at Istituto Astrofisica Spaziale of IC.N.R. in Rome and Mission Scientist of BeppoSAX for the Ital­ian space agency (ASI). His main research areas areGamma-Ray Bursts and Active Galactic Nuclei, as well as thedevelopment of instrumentation for high energy astrophysics.He has led several observing programs with X-ray satellitessince 1980.

Letters, opinions, comments... please send them to:Europhysics News, 34 rue Marc Seguin, BP-2136,68060 Mulhuose Cedex, Franceemail: epn@evhr.net

32 europhysics news JANUARY/FEBRUARY 2002

europhysics news recruitmentContact Susan Mackie • EDP Sciences • 250, rue Saint Jacques • F-75005 Paris • FrancePhone +33 (0)1 5542 80 51 • tax +33 (0)1 46 33 21 06 • e-mail mackie@edpsciences.org

SWISS LIGHT SDUlCE!lJ'JI

c::{yJ-=1 b PAUL SCHERRER INSTITUT ~W~Ir.

RESEARCH AT THE SWISS LIGHT SOURCE

First Call for Proposals

The Swiss Light Source SLS provides access to the facility for Swiss and internationalusers. Researchers using synchrotron radiation are invited to submit proposals forexperiments to be carried out in the year 2002. Beam time requests must reach the SLSat the address given below as soon as possible and no later than March 8, 2002.Application forms and instructions can be obtained by written or email contact at theaddress given below or can be downloaded from the SLS web site www.psi.ch/sls.

The proposals will be selected by an independent international peer review committeeon the basis of scientific criteria. Successful applicants will be allocated access free ofcharge, including logistic, technical, and scientific support.

General description of the facility

The Swiss Light Source, SLS, is an advanced synchrotron radiation facility inoperation since the fall of 2001. The stored electron beam with an energy of 2.4 GeVhas a very low emittance, allowing for the implementation of small-gap insertiondevices. SLS has three undulator beamlines and one wiggler beamline available for useduring the first two years of its user operation. The beamlines are equipped withstate-of-the-art facilities for high-resolution photoelectron spectroscopy andmicroscopy, X-ray diffraction analysis of materials, and protein crystallography.Detailed information about the facility and the experimental stations including theirspecific time scales is available on the SLS web site http://www.psi.ch/sls.

Address: Swiss Light Source, Paul Scherrer Institut,CH-5232 Villigen PSI, Switzerland,Fax: +41 (56) 310 3151, Email: sls@psi.ch, Phone: +41 (56) 310 3178

Contact: Dr. Heinz J. Weyer, te!': +41 (56) 310 3494,email: Heinz-josef.weyer@psi.ch

Scientific director: Prof. Dr. Friso van der Veen, te!.: +41 (56) 310 5118

.J.}. The University of lausanne (UNIL) lPfIr.9lYIiil UdCand the Swiss Federal Institute of 1 \I...;..JTechnology lausanne (EPFL) =~=.::~~

Professorship in the area ofObservational Cosmology

A substantial expansion in the basic sciences is planned at the Lausannesite, induding a significant reinforcement of physics, chemistry andmathematics and a major new effort in biological sciences and engi­neering. As part of this broad program, the UNIL. in dose collaborationwith the EPFL. anticipates the appointment of a full professor in thearea of Observational Cosmology. Depending on the age and qualifi­cations of the selected candidate, the appointment could also be madeat the tenure-track assistant professor level. In 2003, heJshe will beco­me a faculty member at the EPFL. with research activities based at theGeneva Observatory in Sauvemy (http://obswww.unige.ch). a well­known institution with a historical tradition of excellence.

We seek outstanding individuals with an excellent academic recordand research achievements. The successful applicant will initiateindependent, creative research programs and participate in bothundergraduate and graduate teaching.

Starting date: October 1st, 2002 or as agreed. Applications fromwomen candidates are highly welcomed.

For further information, please contact: professor W.-D. Schneider(wolf-dieter.schneider@ipmc.unil.ch) or professor G. Margaritondo(giorgio.margaritondo@epfl.ch) and look at http://wNw-sphys.unil.chIand http://dpwww.epfl.chl

Applications, including curriculum vitil! with publication list, briefstatement of research interests and the names and addresses (inclu­ding e-mail) of at least five references, must be sent beforeFebruary 28. 2002 to the Dean of the Faculty of Sciences,Universite de Lausanne, College Propedeutique, CH-1015Lausanne. Switzerland.

Call for Applicants to Attend a Three-dayCourse/Seminar on Quantum Information Systems

Postdoctoral physicists and senior graduate students interested inQuantum Information Systems (QIS) research are invited to apply forfinancial support to attend a three-day seminar/course in Innsbruck,Austria, taught by leading physicists from Europe and the U.S. Successfulapplicants will also be considered for postdoctoral positions in leading U.S.universities involved in QIS research, if desired.

Topics to be discussed include:•Atomic physics• Quantum information theory• Quantum optics•Semiconductor nanostructures•Spintronics•Superconductivity

Invited speakers include D. Awschalom (co-chair), D. Bouwmeester,H. Briegel, M. Devoret, A. Ekert, J. Kimble, L. Kouwenhoven, D. Loss(co-chair), U. Vazirani, and P. Zoller.

Although all applicants will be considered, particular interest is inresearchers at the post-doctoral level with experimental physicsbackground in the areas listed above. Successful applicants will receivefinancial support for all registration, hotel, and meal expenses, plus anallowance for travel within Europe. The workshop will be held at thefive-star Europa Tirol Hotel (hltp:/Iwww.europatyrol.coml) in charmingInnsbruck, Austria. Information and an application form are athttp://www.wtec.orgIQIS/. For more information contact:sgould@wtec.org. The closing date for applications is March 15, 2002.

The school is being organized by the World Technology Evaluation Genterof Baltimore, Maryland, USA and is supported by the U.S. National ScienceFoundation and the Defense Advanced Research Projects Agency.

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EURESCOConferences

A Programme of the European Science Foundationwith the 5upport of the European Commission

Cluster - Surface Interactions:EuroConference on Functional ClustersGranada, Spain, 1-6 June 2002

Chair: K.-H. Meiwes-Broer (Rostock, D); Vice-Chair: A. Perez (Lyon, F)

SPEAKERS WILL INCLUDEA Andriotis (Heraklion, EL); J.-P. Ansermet (Lausanne, CH);U. Banin (Jerusalem, IL); C. Binns (Leicester, UK);S. Brown (Christchurch, NZ);E. Campell (Goethenburg, Si; G. Gerber (Wurzburg, D);W Harbich (Lausanne, CH); M. Hou (Bruxelles, B); H. H6vel (Dortmund, D);U. Landman (Atlanta, US); J. Lerme (Lyon, F); 1. Mark (Innsbruck, A);P. Melinon (Lyon, F); G. Pastor (Toulouse, F); A Perez (Lyon, F);M.-P. Pileni (Paris, F); R. R6hlsberger (Rostock, D); J. Ruitenbeek (Leiden, NL);W-D. Schneider (Lausanne, CH); V. Senz (Rostock, D);D. Tomanek (SeOUl, KR); F. Vallee (Bordeaux, F); B. von Issendorff (Freiburg, D);W Wernsdorfer (Grenoble, F); W Wurth (Hamburg, D).

SCOPE OF THE CONFERENCE---- -- ----- --- -

A vast variety of experiments and calculations has shown that isolated metalclusters possess many interesting features which distinctly differ from every­thing which is known from the surfacelsolid state physics on the one hand andfrom the atomic and molecular physics on the other. E.g., metal (as well assemiconductor or carbon) clusters exhibit electronic level structures whichoften change completely when the number of atoms changes by only one unit.Correspondingly the work functions are very sensitive to the exact number ofatoms as well as the chemical reactivities or magnetism. For a possible techni­cal application of these new properties it is prerequisite to bring the clustersinto an environment, which could be a surface or an encapsulating matrix. Theinteraction with the contact medium might change their distinctive characteris­tics. Thus the physics of the c1uster-on-surface system is of fundamentalimportance. Due to the highly interdisciplinary nature of this field, which com­prises features from different parts of physics (solid state, magnetism, quantummechanics, optics, thermodynamics, surface physics, etc.), chemistry, electro­nic engineering, and, so far to a lower extent, also biology, it is necessary toconstitute a discussion which allows a merging of the manifold of features.

Deadline for Applications: 12 March 2002

Future Perspectives of SuperconductingJosephson Devices: EuroConference on the Physicsand Applications of the Intrinsic Josephson Effect

Pomrnersfelden, Germany, 29 June - 4 July 2002

Chair: P. Muller (Erlangen, D)

SPEAKERS WILL INCLUDE

L.M. Bulaevskii (LosAlamos, US); C. Cosmelli (Rome, I); G. Filatrella (Salemo, I);C.E. Gough (Birmingham, UK); C. Helm (Zurich, CH); K. Hirata (Tsukuba, J);I. Iguchi (Tokyo, J); J. Keller (Regensburg, D); R. Kleiner (Tubingen, D);VV Kurin (Nizhny Novgorod, RU); AE. Koshelev (Argonne, US);Y.1. Latyshev (Moscow, RU); H.J. Lee (Pohang, KR); A Maeda (Tokyo, J);K. Nakajima (Tohoku, J); G. Ohya (Utsunomiya, J); N.F. Pedersen (Lyngby,OK); S. Sakai (Tsukuba, J); P. Seidel (Jena, D); M. Tachiki (Tsukuba, J);AV. Ustinov (Erlangen, D); H.B. Wang (Tohoku, Sendai, J);PA Warburton (London, UK); D.winkler (G6teborg, Si; PH Wu (Nanjing, CN);1. Yamashita (Tohoku, Sendai, J); A Yurgens (G6teborg, S).

SCOPE OF THE CONFERENCE

The aim of this conference is to focus on the intrinsic Josephson effects and plasmaoscillations in high-Tc superconductors. Starting from the basic physics, recentprogress in the properties of intrinsic Josephson junctions will be summarized.Special topics are vortex dynamics of Josephson stacks and phase-lockeffects of Josephson oscillations. Applications include high-frequency electro­nics and single charge transport devices. Complementary topics will be quantumcomputation with superconducting circuits and recent developments of low-TcJosephson devices.

Deadline for Applications: 2 April 2002

High Performance Fibers:EuroConference on Self-Assembling Fibrous MaterialsBad Herrenalb, Germany, 7-12 September 2002

Chair: C. Viney (Edinburgh, UK)

Sl'EAKERS WILL INCLUD~ (list to be completed)

D. Filzmaurice (National University of Ireland, Dublin, IRL);JA Preece (University of Birmingham, UK);D.N. Woolfson (University of Sussex, UK);R. Zentel (Johannes Gutenberg-University, Mainz, D).

SCOPE OF THE CONFERENCEThere is growing interest in self-assembling materials: synthesis andprocessing are becoming more integrated, using molecules that are desi­gned to organise spontaneously and hierarchically into complex structures inappropriate environments. Self-assembly can reduce the need for energy­intensive or environmentally damaging processing steps. Fibrous structuresproduced by self-assembly can be solid or hollow, inorganic or organic,natural or synthetic. Significant inspiration for self-assembled fibrous materialscomes from nature, where all materials and devices are built up underambient conditions and from aqueous solution, using molecules that are welladapted to this purpose. A unique, multidisciplinary group of experts,covering a wide remit of active research in fibre self-assembly, will bebrought together by this conference. Topics addressed will range frominorganic crystal engineering, to organic polymer synthesis, to naturalsystems that offer useful lessons on the science and practice of fibre self­assembly.

Deadline for Applications: May 2002

Quantum Optics: EuroConference on QuantumAtom Optics: From Quantum Science to Technology

San Feliu de Guixols, Spain, 21-26 September 2002

Chair: 1. Esslinger (Zurich, CH)

SPEAKERS WILL INCLUDE

A. Aspect (Orsay, F); K. Burnett (Oxford, UK); M. Chekhova (Moscow, RU);N. Davidson (Rehovot, IL); M. Drewsen (Aarhus, OK); M. Ducloy (Paris, F);M. Fleischhauer (Kaiserslautern, D); N. Gisin (Geneva, CH);R. Grimm (Innsbruck, A); M. Inguscio (Florence, I); S. Inoye (Boulder, US);D. Jaksch (Innsbruck, A); H. Katori (Kawasaki, Japan);C. Kurtsiefer (Munich, D); G. Leuchs (Erlangen, D);K. Moelmer (Aarhus, OK); A Minguzzi (Pisa, I);G. Morigi (Garching, D); S. Stenholm (Stockholm, S);K.-A. Suominen (Turku, FIN); M. Weidemuller (Heidelberg, D);W. Zwerger (Munich, D).

SCOPE OF THE CONFERENCE

Quantum Optics has proven to be a uniquely dynamic field in physicscapable of taking up new ideas and developments. At the centre of QuantumOptics is the study of quantum phenomena and quantum processes, whichare now becoming increasingly relevant for emerging technologies. The2002 Quantum Optics conference will have its emphasis on the coherentmanipUlation of quantum systems and on the quantum physics of coherentmatter, with high level contributions from leading research groups. Sessionswill be devoted to topical subjects such as quantum atom optics, atomlasers, molecules and interactions, and quantum information processing.A key session will be on technologies emerging from Quantum Optics.

Deadline for Applications: May 2002

Conferences are open to researchers world-wide, whether from industry or academia. Participation wilJ be limited to 100.The registration fee covers fulJ board and lodging. Grants are available, in particular for nationals from EU or Associated States

under 35 (EC support from the High Level Scientific Conferences Activity)Scientific programme & on-line application form available at: http://www.esf.org/euresco

or contact: Dr. J. Hendekovic, EURESCO Office, ESF, 1 quai Lezay-Marnesia, 67080 Strasbourg Cedex, FranceTel. (33) 388 76 71 35 Fax. (33) 388366987 Email: euresco@esf.org

7-11 April Brighton

The Physics Congress 2002

Physics for all at

ongressThe Institute of Physics' landrnark event for physicists world-wide

April 7-11, 2002 The Brighton Centre andMetropole Hotel, Brighton, UK

An extensive programme of scientific conferences (includingCMD19/CMMP2002) combined with exhibitions, meetings on science

policy, activities for physics students and a lively social programme makesCongress the best place for physicists to meet their colleagues and to discuss

their subject. A single fee covers most conferences (£101day Institute studentmembers, £55/day Institute members; £83/day non-members). Many events

are free of charge. Contact the Conferences Department at the Institute ofPhysics address below.

ConferencesEuropean Physical Society's CMD19 with CMMP2002, Nuclear and ParticlePhysics Division conference, Speech recognition event, Third UK workshopon diamond and diamond-like carbon, Structural failures andcrashworthiness, Invention and innovation, Teaching physics post-l 9,Talking physics, and The life and work of Paul Dirac.

The Physics ExpoA refreshingly new and professionally organised showcase featuring leadingsuppliers displaying the latest technologies. Find out what's new in physics­based industry, discover the latest ideas, tryout new techniques and beinspired!

Plenary lecturesLeading speakers address today's issues in physics, industry and science policy.

Further details, as they become available, are on the Web site atcongress.iop.org

Facilities Forum - is Policy for Big Science Working?Discuss the strengths and weaknesses of current British and European arrangements

for the construction of new large experimental scientific facilities.

Women in Physics - Conclusions of the IUPAP ConferenceA UK response to issues raised at the International Union of Pure and Applied Physics

Conference on Women in Physics.

Activities for physics students and recent graduatesPoster and lecture competitions, social events and more.

Public and schools programmeInteractive physics for all; a cyber-cafe; and a Family Fun Physics Day. Throughout the week an extensive programmeof talks and demonstrations looking at physics from inside the human body to outer space and everything in between.

The Institute of Physics, 76 Portland Place, London WIB lNTTel: +44 (0)20 7470 4800 Fax: +44 (0)2074704900Emai1: conferences@iop.org or congress@iop.orgWeb: physica.iop.orgllOP/Conf81CMD191 or cong......iop.org